Remove dead-code

[IvanCherepov]

Addresses the most of dead-code from #1719

➜ spicedb git:(main) deadcode -test ./... | grep -v pkg

internal/datasets/subjectsetbytype.go:93:28: unreachable func: SubjectByTypeSet.Len
internal/datastore/crdb/options.go:329:6: unreachable func: DebugAnalyzeBeforeStatistics
internal/datastore/mysql/options.go:218:6: unreachable func: DebugAnalyzeBeforeStatistics
internal/datastore/postgres/log_tracer.go:13:25: unreachable func: tracingLogger.Log
internal/datastore/postgres/options.go:341:6: unreachable func: DebugAnalyzeBeforeStatistics
internal/datastore/postgres/options.go:348:6: unreachable func: WithQueryInterceptor
internal/datastore/postgres/common/pgx.go:166:6: unreachable func: ConnectWithInstrumentation
internal/developmentmembership/trackingsubjectset.go:59:32: unreachable func: TrackingSubjectSet.RemoveFrom
internal/dispatch/combined/combined.go:129:6: unreachable func: RemoteDispatchTimeout
internal/graph/errors.go:59:6: unreachable func: NewAlwaysFailErr
internal/graph/errors.go:73:34: unreachable func: RelationNotFoundError.NamespaceName
internal/graph/errors.go:78:34: unreachable func: RelationNotFoundError.NotFoundRelationName
internal/graph/errors.go:82:34: unreachable func: RelationNotFoundError.MarshalZerologObject
internal/graph/errors.go:87:34: unreachable func: RelationNotFoundError.DetailsMetadata
internal/graph/errors.go:95:6: unreachable func: NewRelationNotFoundErr
internal/graph/errors.go:136:6: unreachable func: NewRelationMissingTypeInfoErr
internal/graph/errors.go:179:6: unreachable func: NewUnimplementedErr
internal/graph/graph.go:30:24: unreachable func: ExpandResult.ResultError
internal/graph/graph.go:38:6: unreachable func: AlwaysFailExpand
internal/logging/logger.go:39:6: unreachable func: Log
internal/logging/logger.go:43:6: unreachable func: Print
internal/logging/logger.go:47:6: unreachable func: Printf
internal/middleware/dispatcher/dispatcher.go:28:6: unreachable func: FromContext
internal/middleware/dispatcher/dispatcher.go:38:6: unreachable func: MustFromContext
internal/services/shared/errors.go:109:6: unreachable func: AsValidationError
internal/services/shared/interceptor.go:16:50: unreachable func: WithUnaryServiceSpecificInterceptor.UnaryInterceptor
internal/services/v0/developer.go:26:6: unreachable func: RegisterDeveloperServer
internal/testfixtures/generator.go:18:6: unreachable func: RandomObjectID

➜ spicedb git:(ivan-remove-dead-code-1719) deadcode -test ./... | grep -v pkg

internal/graph/errors.go:65:34: unreachable func: RelationNotFoundError.NamespaceName
internal/graph/errors.go:70:34: unreachable func: RelationNotFoundError.NotFoundRelationName
internal/middleware/dispatcher/dispatcher.go:28:6: unreachable func: FromContext
internal/services/shared/errors.go:109:6: unreachable func: AsValidationError
internal/services/shared/interceptor.go:16:50: unreachable func: WithUnaryServiceSpecificInterceptor.UnaryInterceptor

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❌ @IvanCherepov
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[vroldanbet]

Hey Ivan, appreciate the PR, but we can't blindly accept this. Many of these functions are exported, which means that Go code importing SpiceDB would break. I'd suggest removing only unexported code to begin with.