feat: next release from main branch is 1.40.0 (#1166)

Author: jinseopkim0

.github/release-please.yml

@@ -19,3 +19,8 @@ branches:
     releaseType: java-backport
     versioning: always-bump-minor
     branch: 1.38.x
+  - handleGHRelease: true
+    releaseType: java-backport
+    versioning: always-bump-minor
+    tagPullRequestNumber: true
+    branch: 1.39.x

.github/sync-repo-settings.yaml

@@ -67,6 +67,19 @@ branchProtectionRules:
       - dependencies (11)
       - clirr
       - cla/google
+  - pattern: 1.39.x
+    isAdminEnforced: true
+    requiredApprovingReviewCount: 1
+    requiresCodeOwnerReviews: true
+    requiresStrictStatusChecks: false
+    requiredStatusCheckContexts:
+      - checkstyle
+      - units (8)
+      - units (11)
+      - dependencies (8)
+      - dependencies (11)
+      - clirr
+      - cla/google
 permissionRules:
   - team: yoshi-admins
     permission: admin