Cannot compile ANY custom pluggable validation

### Description

I've been trying for a few weeks now to create a custom pluggable validation and have that instead of DefaultValidation. The code is as below:

```
package main

import (
"fmt"
"github.com/golang/protobuf/proto"
"testing"

validation "github.com/alfredom/fabric/core/handlers/validation/api"
. "github.com/alfredom/fabric/core/handlers/validation/api/capabilities"
. "github.com/alfredom/fabric/core/handlers/validation/api/identities"
. "github.com/alfredom/fabric/core/handlers/validation/api/policies"
. "github.com/alfredom/fabric/core/handlers/validation/api/state"
"github.com/hyperledger/fabric-protos-go/common"
"github.com/hyperledger/fabric/protoutil"
"github.com/pkg/errors"
"github.com/stretchr/testify/require"
)

// SampleValidationPlugin is an example for a validation plugin,
// and is used to exercise the dependencies that the plugin validator provides
type SampleValidationPlugin struct {
t *testing.T
d IdentityDeserializer
c Capabilities
sf StateFetcher
pe PolicyEvaluator
}

// NewSampleValidationPlugin returns an instance of a validation plugin setup
// for assertions.
func NewSampleValidationPlugin(t *testing.T) *SampleValidationPlugin {
return &SampleValidationPlugin{t: t}
}

type MarshaledSignedData struct {
Data []byte `protobuf:"bytes,1,opt,name=data,proto3" json:"data,omitempty"`
Signature []byte `protobuf:"bytes,2,opt,name=signature,proto3" json:"signature,omitempty"`
Identity []byte `protobuf:"bytes,2,opt,name=identity,proto3" json:"identity,omitempty"`
}

func (sd *MarshaledSignedData) Reset() {
*sd = MarshaledSignedData{}
}

func (*MarshaledSignedData) String() string {
panic("implement me")
}

func (*MarshaledSignedData) ProtoMessage() {
panic("implement me")
}

func (p *SampleValidationPlugin) Validate(block *common.Block, namespace string, txPosition int, actionPosition int, contextData ...validation.ContextDatum) error {
fmt.Printf("Validation is starting")
txData := block.Data.Data[0]
txn := &MarshaledSignedData{}
err := proto.Unmarshal(txData, txn)
require.NoError(p.t, err)

// Check if the chaincode is instantiated
state, err := p.sf.FetchState()
if err != nil {
return err
}
defer state.Done()

results, err := state.GetStateMultipleKeys("lscc", []string{namespace})
if err != nil {
return err
}

_ = p.c.PrivateChannelData()

if len(results) == 0 {
return errors.New("not instantiated")
}

// Check the identity can be properly deserialized
identity, err := p.d.DeserializeIdentity(txn.Identity)
if err != nil {
return err
}

identifier := identity.GetIdentityIdentifier()
require.Equal(p.t, "SampleOrg", identifier.Mspid)
require.Equal(p.t, "foo", identifier.Id)

sd := &protoutil.SignedData{
Signature: txn.Signature,
Data: txn.Data,
Identity: txn.Identity,
}
// Validate the policy
pol := contextData[0].(SerializedPolicy).Bytes()
err = p.pe.Evaluate(pol, []*protoutil.SignedData{sd})
if err != nil {
return err
}
fmt.Printf("Validation finished")
fmt.Printf("Hello from Alfredo")
return nil
}

func (p *SampleValidationPlugin) Init(dependencies ...validation.Dependency) error {
fmt.Println("Inializating")
for _, dep := range dependencies {
if deserializer, isIdentityDeserializer := dep.(IdentityDeserializer); isIdentityDeserializer {
p.d = deserializer
}
if capabilities, isCapabilities := dep.(Capabilities); isCapabilities {
p.c = capabilities
}
if stateFetcher, isStateFetcher := dep.(StateFetcher); isStateFetcher {
p.sf = stateFetcher
}
if policyEvaluator, isPolicyFetcher := dep.(PolicyEvaluator); isPolicyFetcher {
p.pe = policyEvaluator
}
}
if p.sf == nil {
p.t.Fatal("stateFetcher not passed in init")
}
if p.d == nil {
p.t.Fatal("identityDeserializer not passed in init")
}
if p.c == nil {
p.t.Fatal("capabilities not passed in init")
}
if p.pe == nil {
p.t.Fatal("policy fetcher not passed in init")
}
return nil
}
```

I have then added this to my core.yaml file after having compiled it as a plugin (.so):
```
custom:
name: CustomValidation
library: /etc/hyperledger/fabric/plugins/test_validation_no_flags.so
```
and started up my network.sh file with the command network.sh up.

Finally, I get the error:

To give a bit more context, this is my go.mod:

```
module main
go 1.20

replace github.com/alfredom/fabric => /home/alfredo/go/src/github.com/alfredom/fabric

replace github.com/willf/bitset v1.2.1 => github.com/bits-and-blooms/bitset v1.2.1

require (
github.com/alfredom/fabric v0.0.0-00010101000000-000000000000
github.com/golang/protobuf v1.5.3
github.com/hyperledger/fabric v2.1.1+incompatible
github.com/hyperledger/fabric-protos-go v0.3.0
github.com/pkg/errors v0.9.1
github.com/stretchr/testify v1.8.2
)

require (
github.com/Knetic/govaluate v3.0.1-0.20171022003610-9aa49832a739+incompatible // indirect
github.com/davecgh/go-spew v1.1.1 // indirect
github.com/fsnotify/fsnotify v1.4.9 // indirect
github.com/hashicorp/hcl v1.0.0 // indirect
github.com/hyperledger/fabric-amcl v0.0.0-20210603140002-2670f91851c8 // indirect
github.com/hyperledger/fabric-lib-go v1.0.0 // indirect
github.com/magiconair/properties v1.8.1 // indirect
github.com/miekg/pkcs11 v1.1.1 // indirect
github.com/mitchellh/mapstructure v1.4.3 // indirect
github.com/onsi/ginkgo v1.16.5 // indirect
github.com/pelletier/go-toml v1.8.1 // indirect
github.com/pmezard/go-difflib v1.0.0 // indirect
github.com/spf13/afero v1.3.1 // indirect
github.com/spf13/cast v1.3.1 // indirect
github.com/spf13/jwalterweatherman v1.1.0 // indirect
github.com/spf13/pflag v1.0.5 // indirect
github.com/spf13/viper v1.7.0 // indirect
github.com/stretchr/objx v0.5.0 // indirect
github.com/subosito/gotenv v1.2.0 // indirect
github.com/sykesm/zap-logfmt v0.0.4 // indirect
go.uber.org/atomic v1.7.0 // indirect
go.uber.org/multierr v1.6.0 // indirect
go.uber.org/zap v1.19.0 // indirect
golang.org/x/crypto v0.1.0 // indirect
golang.org/x/net v0.7.0 // indirect
golang.org/x/sys v0.5.0 // indirect
golang.org/x/text v0.7.0 // indirect
google.golang.org/genproto v0.0.0-20220718134204-073382fd740c // indirect
google.golang.org/grpc v1.48.0 // indirect
google.golang.org/protobuf v1.28.1 // indirect
gopkg.in/ini.v1 v1.51.0 // indirect
gopkg.in/yaml.v2 v2.4.0 // indirect
gopkg.in/yaml.v3 v3.0.1 // indirect
)

```
--------------------------------------
In order to ensure that I am using the same compiler options, I have cloned fabric-tools container, and made an image out of it. Then, I started my own container which I use only to build my plugin in .so (this takes care of using the right version of glibc, go, and various other options). When the file is compiled, I then move it in the folder where I have mounted my volume for the ./network.sh to locate the file.
In this particular instance, my error is related to `google.golang.org/protobuf/internal/detrand`, however, before this was `google.golang.org/protobuf`, and earlier `runtime/internal/atomic`. In essence, a new error always pop-ups.

**Things I noticed**: although I am using a clone of fabric 2.5.0 repo, I still need to import "github.com/hyperledger/fabric/protoutil". If I don't do this, the file won't build as the compiler will complain that:
```
imports github.com/alfredom/fabric/protoutil
vendor/github.com/alfredom/fabric/protoutil/commonutils.go:17:2: use of internal package github.com/hyperledger/fabric/internal/pkg/identity not allowed
```

It seems like, there might be a problem with google-protobuf package as that is the one that seems to be complaining the most. However, I have made sure that my go.mod is identical to the one used in the fabric branch 2.5.0, thus I have no idea why this is happening.

Lastly, I tried building a plugin out of a hello world plugin, and that worked (it complained about missing specific interfaces, but that was expected as I didn't add PluginFactory and all that). However, I'd need to add dependencies specifically to protobuf to unpack my message and as soon as I do that everything would break.
--------------------------------------
**Useful Info**: I am using a clone of 2.5.0 Fabric branch, the docker images are also up to date.

### Steps to reproduce

NB: this uses the fabric samples with 3 orgs.

1. Commit the existing container to a new Docker image:
docker commit :

2. Run the container
docker run -d --name : tail -f /dev/null

3. Install necessary packages
docker exec -it sh
then type su and install vim and git-build-essentials.
su
apt-get install -y curl git build-essential
apt-get install -y curl vim

4. Copy cloned repository to the container GOPATH (NB: adjust paths accordingly)
docker cp /home/alfredo/go/src/github.com/alfredom/fabric :/opt/gopath/src/github.com/fabric

5. Copy plugin to the container
docker cp /home/alfredo/go/src/github.com/alfredom/fabric-samples/test-network-3-orgs/custom_validation/test_validation.go 5f2397807828:/opt/gopath/src/github.com/hyperledger/fabric/peer/test_validation.go

6. Run go mod and edit
go mod init main
echo 'replace github.com/alfredom/fabric => /opt/gopath/src/github.com/fabric' >> go.mod (adjust this accordingly)
echo 'replace github.com/willf/bitset v1.2.1 => github.com/bits-and-blooms/bitset v1.2.1' >> go.mod

7. Build the plugin
go build -buildmode=plugin -o test_validation_no_flags.so test_validation.go

8. Copy it out to the destination folder (adjust accordingly)
docker cp :/opt/gopath/src/github.com/hyperledger/fabric/peer/test_validation_no_flags.so /home/alfredo/go/src/github.com/alfredom/fabric-samples/test-network-3-orgs/custom_validation/test_validation_no_flags.so

9. ./network.sh down; ./network.sh up; then show logs or alternatively change the following line in the network.sh file DOCKER_SOCK="${DOCKER_SOCK}" ${CONTAINER_CLI_COMPOSE} ${COMPOSE_FILES} up -d 2>&1 to DOCKER_SOCK="${DOCKER_SOCK}" ${CONTAINER_CLI_COMPOSE} ${COMPOSE_FILES} up.