ci: declare accepted secrets on dependabot rebase workflow

[nickolas-dimitrakas]

Background

• Callers of this reusable workflow currently have to use secrets: inherit to run it, since it doesn't declare which secrets it accepts.

What Has Changed

• Declares MP_SEMANTIC_RELEASE_BOT, GPG_PRIVATE_KEY, and GPG_PASSPHRASE under on.workflow_call.secrets, matching what the job already references. This lets callers pass only those specific secrets explicitly instead of inheriting their whole secret set.

Checklist

• I have performed a self-review of my own code.
• I have tested this locally (workflow YAML validated; no behavior change for existing callers using secrets: inherit).

🤖 Generated with Claude Code

[cursor]

PR Summary

Low Risk
Low risk CI configuration update with no logic changes to the underlying workflow jobs.

Overview
Explicitly declares the required secrets (MP_SEMANTIC_RELEASE_BOT, GPG_PRIVATE_KEY, and GPG_PASSPHRASE) on the workflow_call trigger in dependabot-rebase-development.yml. This allows calling workflows to pass specific secrets explicitly instead of relying on secrets: inherit.

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[nickolas-dimitrakas]

Closing — the only caller of this workflow (mparticle-android-sdk's dependabot-rebase-branch.yml) is being removed instead of updated to use explicit secrets, so this change is no longer needed.