deps: updates required checks list in github (#2136)

* deps: updates required checks list in github

* deps: updates snippet and system checks in github to remove 3.9

* changes the order of two items in the list.

Author: chalmerlowe

.github/sync-repo-settings.yaml

@@ -10,14 +10,10 @@ branchProtectionRules:
   requiresStrictStatusChecks: true
   requiredStatusCheckContexts:
     - 'Kokoro'
-    - 'Kokoro snippets-3.8'
-    - 'Kokoro snippets-3.12'
-    - 'Kokoro system-3.8'
     - 'Kokoro system-3.12'
+    - 'Kokoro snippets-3.12'
     - 'cla/google'
     - 'Samples - Lint'
-    - 'Samples - Python 3.7'
-    - 'Samples - Python 3.8'
     - 'Samples - Python 3.9'
     - 'Samples - Python 3.10'
     - 'Samples - Python 3.11'
@@ -28,8 +24,7 @@ branchProtectionRules:
   requiresStrictStatusChecks: true
   requiredStatusCheckContexts:
     - 'Kokoro'
-    - 'Kokoro snippets-3.8'
     - 'cla/google'
     - 'Samples - Lint'
-    - 'Samples - Python 3.7'
-    - 'Samples - Python 3.8'
+    - 'Samples - Python 3.9'
+    - 'Samples - Python 3.10'