build: eliminate usage of `metamorphic_disable` `gotag`

The use of non-default `gotags` requires re-compiling the Go SDK and all dependent packages. Unless we *must* use these, they should be removed and then we'll save on CI costs.

```
cockroach$ rg 'gotags ='
pkg/sql/schemachanger/scpb/BUILD.bazel
70: gotags = ["generator"],
95: gotags = ["generator"],

pkg/sql/schemachanger/scop/BUILD.bazel
37: gotags = ["generator"],

pkg/sql/colexec/execgen/cmd/execgen/BUILD.bazel
85: gotags = ["metamorphic_disable"],

pkg/acceptance/BUILD.bazel
55: gotags = ["acceptance"],

pkg/compose/BUILD.bazel
19: gotags = ["compose"],

pkg/compose/compare/compare/BUILD.bazel
14: gotags = ["compose"],

pkg/kv/kvpb/gen/BUILD.bazel
14: gotags = ["metamorphic_disable"],

```

Epic: CRDB-17171

Jira issue: CRDB-38284