Reuse values between namespaces

This is the reorganization proposed by the application configuration change [2]

Note this also adapts the make swh-helm-diff to actually execute the diff in the files we are deploying [1].

This also adapts the graphql configmap to align it with other templates (which also to reuse some already defined values).

[1]

[swh] Generate config in production branch for environment staging...
Switched to branch 'reuse-values-between-namespaces'
[swh] Generate config in reuse-values-between-namespaces branch for environment staging...
Switched to branch 'production'
Your branch is ahead of 'origin/production' by 1 commit.
  (use "git push" to publish your local commits)
[swh] Generate config in production branch for environment production...
Switched to branch 'reuse-values-between-namespaces'
[swh] Generate config in reuse-values-between-namespaces branch for environment production...


------------- diff for environment staging -------------

No differences


------------- diff for environment production -------------

No differences

[2] k8s-clusters-conf!30 (merged)