Re-add submission refactor

[mgoerens]

This commit re-introduces the refactor that splits the chart-verifier job into three and switches to using the Submission data structure for storing all information related to a certification pull request.

Initially this work was introduced by #392.

It was later reverted as part of #397 due to timeouts in the full end to end tests.

Following #403 the end to end tests are now running about twice as fast, as a result we do not expect this refactor to cause a timeout anymore.

Since the original introduction of this work, the code that it touches has been only slightly modified, namely by #398 and #405. As a result, the difference between this PR and the original PR is minimal:

diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index d2b6e4c..50ac1a3 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -28,10 +28,8 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v4
 
-      - name: Set up Python 3.x Part 1
-        uses: actions/setup-python@v5
-        with:
-          python-version: "3.10"
+      - name: Set up Python
+        uses: ./.github/actions/setup-python
 
       - name: Set up Python 3.x Part 2
         run: |
@@ -129,10 +127,8 @@ jobs:
           repository: ${{ github.event.pull_request.head.repo.full_name }}
           path: "pr-branch"
 
-      - name: Set up Python 3.x Part 1
-        uses: actions/setup-python@v5
-        with:
-          python-version: "3.10"
+      - name: Set up Python
+        uses: ./.github/actions/setup-python
 
       - name: Set up Python 3.x Part 2
         run: |
@@ -544,10 +540,8 @@ jobs:
           repository: ${{ github.event.pull_request.head.repo.full_name }}
           path: "pr-branch"
 
-      - name: Set up Python 3.x Part 1
-        uses: actions/setup-python@v5
-        with:
-          python-version: "3.10"
+      - name: Set up Python
+        uses: ./.github/actions/setup-python
 
       - name: Set up Python 3.x Part 2
         run: |
@@ -613,6 +607,7 @@ jobs:
         env:
           CHART_ENTRY_NAME: ${{ needs.validate-submission.outputs.chart_entry_name }}
           WEB_CATALOG_ONLY: ${{ needs.validate-submission.outputs.web_catalog_only }}
+          RELEASE_TAG: ${{ needs.validate-submission.outputs.release_tag }}
         run: |
           INDEX_BRANCH=$(if [ "${GITHUB_REF}" = "refs/heads/main" ]; then echo "gh-pages"; else echo "${GITHUB_REF##*/}-gh-pages"; fi) 

Above output comes from: $ git show HEAD --pretty=oneline --name-only | head -n -1 | xargs git --no-pager diff 77bdeff94bb54c0f9c49fd818b75dc7f8a0fa866 --

[komish]

/lgtm