chore(proc): update repo's settings (#8942)

* chore(proc): update repo's settings

remove Java8 from the list of required checks
remove yoshi-admin from admins
exclude sync settings from header check

Author: minherz

.github/header-checker-lint.yml

@@ -37,4 +37,5 @@ sourceFileExtensions:
   - 'yaml'
   - 'yml'
 ignoreFiles:
-  - '.github/auto-label.yaml'
+  - '.github/auto-label.yaml'
+  - '.github/sync-repo-settings.yaml'

.github/sync-repo-settings.yaml

@@ -6,7 +6,6 @@ branchProtectionRules:
   isAdminEnforced: true
   requiredStatusCheckContexts:
     - 'Kokoro CI - Java 11'
-    - 'Kokoro CI - Java 8'
     - 'Kokoro CI - Lint'
     - 'cla/google'
   requiredApprovingReviewCount: 1
@@ -21,5 +20,3 @@ permissionRules:
     permission: push
   - team: devrel-java-admin
     permission: admin
-  - team: yoshi-admins
-    permission: admin