enable dependabot for dependency updates (#11079)

* enable dependabot for dependency updates
* exclude dependabot config from license checks

.github/dependabot.yml

@@ -0,0 +1,8 @@
+version: 2
+updates:
+  - package-ecosystem: "maven"
+    directory: "/"
+    schedule:
+      interval: "daily"
+    ignore:
+      - dependency-name: "com.google.guava:guava"

pom.xml

@@ -1966,6 +1966,7 @@
                                 <exclude>LABELS</exclude>
                                 <exclude>.github/ISSUE_TEMPLATE/*.md</exclude>
                                 <exclude>.github/pull_request_template.md</exclude>
+                                <exclude>.github/dependabot.yml</exclude>
                                 <exclude>git.version</exclude>
                                 <exclude>node_modules/**</exclude>
                                 <exclude>src/**/*.snap</exclude>