[chore] refactor(contrib): remove unused replace directive for gnostic package (#675)

The package `github.com/googleapis/gnostic v0.5.6` does not exist in contrib's generated `go.sum` file. The distro also builds and runs fine without the replace directive. Is this enough to decide the directive is unnecessary?

Co-authored-by: Alex Boten <[email protected]>

Author: andrzej-stencel

distributions/otelcol-contrib/manifest.yaml

@@ -225,8 +225,6 @@ providers:
 
 # When adding a replace, add a comment before it to document why it's needed and when it can be removed
 replaces:
-  # See https://github.com/google/gnostic/issues/262
-  - github.com/googleapis/gnostic v0.5.6 => github.com/googleapis/gnostic v0.5.5
   # See https://github.com/open-telemetry/opentelemetry-collector-contrib/pull/12322#issuecomment-1185029670
   - github.com/docker/go-connections v0.4.1-0.20210727194412-58542c764a11 => github.com/docker/go-connections v0.4.0
   # see https://github.com/mattn/go-ieproxy/issues/45