chore: create 2.13.x branch to track feature prior to dependency refa… (#4317)

…ctor

Change-Id: I1d2f6e78baa6818e2061662602c6e80201cb69c0

Thank you for opening a Pull Request! Before submitting your PR, there are a few things you can do to make sure it goes smoothly:
- [ ] Make sure to open an issue as a [bug/issue](https://togithub.com/googleapis/java-bigtable-hbase/issues/new/choose) before writing your code!  That way we can discuss the change, evaluate designs, and agree on the general idea
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- [ ] Appropriate docs were updated (if necessary)

Fixes #<issue_number_goes_here> ☕️

If you write sample code, please follow the [samples format](
https://togithub.com/GoogleCloudPlatform/java-docs-samples/blob/main/SAMPLE_FORMAT.md).

Author: igorbernstein2

.github/release-please.yml

@@ -65,3 +65,12 @@ branches:
         bigtable-client-core-parent/bigtable-hbase/src/main/java/com/google/cloud/bigtable/hbase/BigtableHBaseVersion.java
     handleGHRelease: true
     branch: 2.12.x
+  - releaseType: java-backport
+    bumpMinorPreMajor: true
+    extraFiles:
+      - >-
+        bigtable-client-core-parent/bigtable-client-core/src/main/java/com/google/cloud/bigtable/config/BigtableVersionInfo.java
+      - >-
+        bigtable-client-core-parent/bigtable-hbase/src/main/java/com/google/cloud/bigtable/hbase/BigtableHBaseVersion.java
+    handleGHRelease: true
+    branch: 2.13.x

.github/sync-repo-settings.yaml

@@ -114,6 +114,20 @@ branchProtectionRules:
       - OwlBot Post Processor
     requiredApprovingReviewCount: 1
     requiresCodeOwnerReviews: true
+  - pattern: 2.13.x
+    isAdminEnforced: true
+    requiredStatusCheckContexts:
+      - 'Kokoro - Test: Binary Compatibility'
+      - 'Kokoro - Test: Code Format'
+      - 'Kokoro - Test: Dependencies'
+      - 'Kokoro - Test: Integration'
+      - 'Kokoro - Test: Java 11'
+      - 'Kokoro - Test: Java 8'
+      - 'Kokoro - Test: Beam Integration'
+      - cla/google
+      - OwlBot Post Processor
+    requiredApprovingReviewCount: 1
+    requiresCodeOwnerReviews: true
 permissionRules:
   - team: yoshi-java-admins
     permission: admin