chore: add release-please config for protobuf-4.x (#2620)

* chore: add release-please config for protobuf-4.x

* chore: generate libraries at Wed Dec  3 19:03:35 UTC 2025

* Change release type from java-backport to java-yoshi

* Refactor release-please.yml to remove redundancy

Removed duplicate bumpMinorPreMajor setting for java-yoshi.

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Co-authored-by: cloud-java-bot <[email protected]>

Author: diegomarquezp

.github/release-please.yml

@@ -50,3 +50,7 @@ branches:
     handleGHRelease: true
     releaseType: java-backport
     branch: 1.140.x
+  - handleGHRelease: true
+    releaseType: java-yoshi
+    branch: protobuf-4.x-rc
+    manifest: true