Update dependabot configuration (#2210)

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#### Summary <!-- Provide a general summary of your changes -->
Update dependabot configuration to only get one PR instead of one per
dependency

#### Work Item(s) <!-- Add the issue number here after the #. The issue
needs to be open and approved. Submitting PRs with no linked issues or
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Fixes #

.github/dependabot.yml

@@ -5,6 +5,10 @@ version: 2
 updates:
 - package-ecosystem: github-actions
   directory: ".github/workflows/"
+  groups:
+    External-Dependencies:
+      applies-to: version-updates
+      dependency-type: "production"
   schedule:
     interval: weekly
   ignore: