`Dry::Validation::Contract` behaves different when defined with a `params Dry::Schema::Params(parent: RawSchema)` vs. `params ParamsSchema`

## Describe the bug

When `Dry::Validation::Contract` contains `params Dry::Schema::Params(parent: RawSchema)` (where `RawSchema` is defined using `Dry::Schema.define do ... end`), it fails to coerce empty Strings into Integers. However, if I define a `ParamsSchema` using `Dry::Schema::Params() do ... end` containing the same param definitions, and add `params ParamsSchema` to my `Dry::Validation::Contract` class, it works as expected.

## To Reproduce

```ruby
require 'dry/types'
require 'dry/schema'
require 'dry/validation'

module Types
include Dry::Types()
end

RawSchema = Dry::Schema.define do
required(:foo).filled(:string)
optional(:bar).maybe(:integer)
end

ParamsSchema = Dry::Schema::Params() do
required(:foo).filled(:string)
optional(:bar).maybe(:integer)
end

class WrappedParamsSchemaValidation < Dry::Validation::Contract

params Dry::Schema::Params(parent: RawSchema)

end

class ParamsSchemaValidation < Dry::Validation::Contract

params ParamsSchema

end

params = {"foo" => "a", "bar" => ""}

p WrappedParamsSchemaValidation.new.call(params)
p ParamsSchemaValidation.new.call(params)
```

## Expected behavior

```
#"a", :bar=>nil} errors={}>
#"a", :bar=>nil} errors={}>
```

## Actual behavior

```
#"a", :bar=>""} errors={:bar=>["must be an integer"]}>
#"a", :bar=>nil} errors={}>
```

## My environment

- Affects my production application: **NO** (the app is not running in production)
- Ruby version: `ruby 3.1.3p185 (2022-11-24 revision 1a6b16756e) [x86_64-linux]`
- dry-types: 1.7.1
- dry-schema: 1.13.1
- dry-validation: 1.10.0