chore: Trigger update for maven credentials (and add comment) (#294)

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### Description
Maven recently changed the credentials required for publishing:

<img width="848" alt="image"
src="https://github.com/cdktf/cdktf-repository-manager/assets/573531/d71a9f57-69ca-4334-bdb1-962dd3071ee1">

As a reminder for future reference, the way publishing works is that we
use publib through github actions within each prebuilt provider
repository. The github action uses maven username and password through
the repository secrets. The secrets there are written by
`cdktf-repository-manager` (this repo) through Terraform. The secrets
that are sent to the repository through Terraform are stored within an
HCP Terraform variable set.

While this PR only adds a comment to the secret, the true change
happened within HCP Terraform. This PR was necessary to trigger the
Terraform plan apply resulting in updating all Prebuilt provider
repositories.

lib/secrets.ts

@@ -71,8 +71,8 @@ export class PublishingSecretSet extends Construct {
       "nuget-api-key",
       "twine-username",
       "twine-password",
-      "maven-username",
-      "maven-password",
+      "maven-username", // Use the user token from https://hashicorp.oss.sonatype.org/#profile;User%20Token (saved in 1Password)
+      "maven-password", // Use the user token password (same as above)
       "maven-gpg-private-key",
       "maven-gpg-private-key-passphrase",
       "maven-staging-profile-id",