Remove token and caching details, being implemented separately

Signed-off-by: Dipti Pai <[email protected]>

rfcs/0006-git-repo-passwordless-auth/README.md

@@ -186,24 +186,3 @@ token](https://docs.github.com/en/apps/creating-github-apps/authenticating-with-
 This token is then used as the password and [`x-access-token` as the username](https://docs.github.com/en/apps/creating-github-apps/registering-a-github-app/choosing-permissions-for-a-github-app#choosing-permissions-for-git-access)
 to perform HTTP basic authentication.
 
-### Token Caching and Refreshing
-
-To avoid calling the upstream API for a token during every reconciliation, Flux
-controllers shall cache the token after fetching it. Since GitHub tokens
-self-expire, the cache shall automatically evict the token after it has expired,
-triggering a fetch of a fresh token.
-For GCP, the [`TokenSource`](https://pkg.go.dev/golang.org/x/[email protected]#TokenSource)
-object will be cached, since it automatically handles refreshing an expired
-token and always returns a valid token. Since a `TokenSource` never expires, it
-need not be evicted from the cache.
-While Azure's managed identities subsystem caches the token, it is
-[recommended for the consumer application to implement their own caching](https://learn.microsoft.com/en-us/azure/active-directory/managed-identities-azure-resources/how-to-use-vm-token#token-caching)
-as well.
-The caches for all three providers are separate, i.e. there shall exist a
-dedicated cache for each provider.
-
-Since the proposed authentication methods for GitHub and GCP involve some form
-of credentials stored in a Kubernetes Secret, the cache key can be the Secret's
-`<namespace/name>`. Since authentication for Azure is configured directly via
-the source-controller Deployment, the token can just be stored in a global
-variable, which is refreshed whenever the token expires.