chore: cleanup release-please config

- Remove redundant options already declared at the top level.\n- Remove bumpMinorPreMajor for repositories after the first major release.

Author: diegomarquezp

.github/release-please.yml

@@ -1,23 +1,15 @@
 handleGHRelease: true
 manifest: true
 branches:
-  - bumpMinorPreMajor: true
-    handleGHRelease: true
-    packageName: gcp-lts-bom
-    manifest: true
-    branch: 9.0.x-lts
-  - bumpMinorPreMajor: true
-    handleGHRelease: true
-    packageName: gcp-lts-bom
-    manifest: true
-    branch: 8.0.x-lts
-  - bumpMinorPreMajor: true
-    handleGHRelease: true
-    packageName: gcp-lts-bom
-    manifest: true
-    branch: 7.0.x-lts
-  - bumpMinorPreMajor: true
-    handleGHRelease: true
-    packageName: gcp-lts-bom
-    manifest: true
-    branch: 6.0.x-lts
+    - bumpMinorPreMajor: true
+      packageName: gcp-lts-bom
+      branch: 9.0.x-lts
+    - bumpMinorPreMajor: true
+      packageName: gcp-lts-bom
+      branch: 8.0.x-lts
+    - bumpMinorPreMajor: true
+      packageName: gcp-lts-bom
+      branch: 7.0.x-lts
+    - bumpMinorPreMajor: true
+      packageName: gcp-lts-bom
+      branch: 6.0.x-lts