github: submodules-update: Port in all the releasehub code & tweak

We want to *check* if there are any changes and only make a branch and add
commits if so.  The upstream code has no option for this, so use it as
a starting point instead.

Specifically this is based on:

https://github.com/releasehub-com/github-action-create-pr-parent-submodule/blob/main/action.yml
aff9d0978a9bbcbc2961d621d5b108c4b46db5e7

* We need 'success' from the *step* to be when there ARE changes, and that
  is in the special github output.
* In order for the whole job *not* to fail in the 'step check_for_changes
  says it failed' case we need it to have `continue-on-error: true`.

.github/workflows/submodule-update.yml

@@ -6,9 +6,6 @@ on:
   push:
     branches: [ develop ]
 
-###############
-# Set the Job #
-###############
 jobs:
   check_submodules:
     name: Pull Request for updated submodules
@@ -20,21 +17,66 @@ jobs:
       OWNER: 'EDCD'
 
     steps:
-      ##########################
+      - uses: actions/checkout@v2.4.0
-      # Checkout the code base #
-      ##########################
-      - name: Checkout EDMC
-        uses: actions/checkout@v2
-
-      ####################################
-      # Run the action against code base #
-      ####################################
-      - name: Check EDMC submodules
-        id: run_action
-        uses: releasehub-com/github-action-create-pr-parent-submodule@v1
         with:
-          github_token: ${{ secrets.GITHUB_TOKEN }}
+          submodules: true
-          parent_repository: ${{ env.PARENT_REPOSITORY }}
+
-          checkout_branch: ${{ env.CHECKOUT_BRANCH}}
+      - name: Update submodules
-          pr_against_branch: ${{ env.PR_AGAINST_BRANCH }}
+        shell: bash
-          owner: ${{ env.OWNER }}
+        run: |
+          git config user.name github-actions
+          git config user.email github-actions@github.com
+          git submodule update --remote
+
+      - name: Check for changes
+        id: check_for_changes
+        continue-on-error: true
+        run: |
+          changes=$(git status --porcelain)
+          if [ -n "${changes}" ];
+          then
+            echo '::set-output changes=true'
+          fi
+          echo '::set-output changes=false'
+          exit 0
+      
+      - name: Create submodules changes branch
+        if: steps.check_for_changes.outputs.changes == 'true'
+        run: |
+          git checkout -b $GITHUB_RUN_ID
+          git commit -am "updating submodules"
+          git push --set-upstream origin $GITHUB_RUN_ID
+
+      - name: Create pull request against target branch
+        if: steps.check_for_changes.outputs.changes == 'true'
+        uses: actions/github-script@v5
+        with:
+          github-token: ${{ inputs.github_token }}
+          script: |
+            await github.rest.pulls.create({
+              owner: '${{ inputs.owner }}',
+              repo: '${{ inputs.parent_repository }}'.split('/')[1].trim(),
+              head: process.env.GITHUB_RUN_ID,
+              base: '${{ inputs.pr_against_branch }}',
+              title: `[Auto-generated] Submodule Updates ${process.env.GITHUB_RUN_ID}`,
+              body: `[Auto-generated] Submodule Updates ${process.env.GITHUB_RUN_ID}`,
+            });
+
+      - name: Add labels
+        if: steps.check_for_changes.outputs.changes == 'true'
+        uses: actions/github-script@v5
+        with:
+          github-token: ${{ inputs.github_token }}
+          script: |
+            const res = await github.rest.issues.listForRepo({
+              owner: '${{ inputs.owner }}',
+              repo: '${{ inputs.parent_repository }}'.split('/')[1].trim(),
+            });
+            const pr = res.data.filter(i => i.title.includes(process.env.GITHUB_RUN_ID));
+            const prNumber = pr[0].number;  
+            await github.rest.issues.addLabels({
+              issue_number: prNumber,
+              owner: '${{ inputs.owner }}',
+              repo: '${{ inputs.parent_repository }}'.split('/')[1].trim(),
+              labels: ['${{ inputs.label }}']
+            });