chore: remove linkage-monitor required check (#552)

Author: chingor13

java-core/.github/sync-repo-settings.yaml

@@ -31,7 +31,6 @@ branchProtectionRules:
   requiredStatusCheckContexts:
     - "dependencies (8)"
     - "dependencies (11)"
-    - "linkage-monitor"
     - "lint"
     - "clirr"
     - "units (8)"
@@ -54,7 +53,6 @@ branchProtectionRules:
   requiredStatusCheckContexts:
   - "dependencies (8)"
   - "dependencies (11)"
-  - "linkage-monitor"
   - "lint"
   - "clirr"
   - "units (7)"
@@ -69,4 +67,4 @@ permissionRules:
 - team: yoshi-java-admins
   permission: admin
 - team: yoshi-java
-  permission: push
+  permission: push