Allow use of dependabot/fetch-metadata

This is a follow-up of apache#339: since `dependabot/fetch-metadata` had eventually released a version that supports grouped updates, we would like to use it in our Dependabot workflow.

Author: ppkarwasz

.github/workflows/dummy.yml

@@ -98,6 +98,8 @@ jobs:
         if: false
       - uses: dawidd6/action-send-mail@d38f3f7cd391cdebfe0d38efc3998b935e951c4f  # v16
         if: false
+      - uses: dependabot/fetch-metadata@ffa630c65fa7e0ecfa0625b5ceda64399aea1b36  # v3.0.0
+        if: false
       - uses: docker/build-push-action@d08e5c354a6adb9ed34480a06d141179aa583294  # v7.0.0
         if: false
       - uses: docker/login-action@4907a6ddec9925e35a0a9e82d7399ccc52663121  # v4.1.0

actions.yml

@@ -268,6 +268,9 @@ dawidd6/action-send-mail:
 delaguardo/setup-graalvm:
   '*':
     keep: true
+dependabot/fetch-metadata:
+  ffa630c65fa7e0ecfa0625b5ceda64399aea1b36:
+    tag: v3.0.0
 dlang-community/setup-dlang:
   '*':
     keep: true