Enable branch protection (#1679)

.asf.yaml

@@ -15,6 +15,9 @@
 # specific language governing permissions and limitations
 # under the License.
 
+# Documentation can be found here:
+# https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=127405038
+
 notifications:
   commits:      [email protected]
   issues:       [email protected]
@@ -28,4 +31,11 @@ github:
     merge: false
     rebase: false
   features:
-    issues: true
+    issues: true
+  protected_branches:
+    master:
+      required_status_checks:
+        # require branches to be up-to-date before merging
+        strict: true
+        # don't require any jobs to pass
+        contexts: []