[ci] Add dispatch actions task to ping tools on tag (wpilibsuite#6755)

Allows automation of tagging of tools on allwpilib tag
Adapted from robotpy

.github/workflows/gradle.yml

@@ -251,3 +251,18 @@ jobs:
         with:
           name: Maven
           path: ~/releases
+
+  dispatch:
+    name: dispatch
+    needs: [combine]
+    runs-on: ubuntu-22.04
+    steps:
+      - uses: peter-evans/repository-dispatch@v3
+        if: |
+          github.repository_owner == 'wpilibsuite' &&
+          startsWith(github.ref, 'refs/tags/v')
+        with:
+          token: ${{ secrets.TOOL_REPO_ACCESS_TOKEN }}
+          repository: wpilibsuite/smartdashboard
+          event-type: tag
+          client-payload: '{"package_name": "allwpilib", "package_version": "${{ github.ref_name }}"}'