Add PRs with release-notes labels to the CHANGELOG (#2067)

Problem: Looking for all the PRs that have the release-notes label is a
manual process

Solution: As a first step in automating this process, we add the list of
PRs to the top of the CHANGELOG so they can be moved in the appropriate
sections

Author: lucacome

.github/release-notes.yml

@@ -0,0 +1,8 @@
+changelog:
+  exclude:
+    labels:
+      - skip-changelog
+  categories:
+    - title: Changelog
+      labels:
+        - release-notes

.github/workflows/release-pr.yml

@@ -18,6 +18,8 @@ permissions:
 jobs:
   release:
     runs-on: ubuntu-22.04
+    permissions:
+      contents: write
     steps:
       - name: Branch
         id: branch
@@ -31,6 +33,13 @@ jobs:
         with:
           ref: ${{ steps.branch.outputs.branch }}
 
+      - name: Get Release Notes
+        id: notes
+        uses: lucacome/draft-release@8a63d32c79a171ae6048e614a8988f0ac3ed56d4 # v1.1.0
+        with:
+          config-path: .github/release-notes.yml
+          dry-run: true
+
       - name: Vars
         id: vars
         run: |
@@ -76,6 +85,7 @@ jobs:
           sed -i -e "s/VERSION = edge/VERSION = ${{ inputs.version }}/g" Makefile
           sed -i "6r .github/CHANGELOG_TEMPLATE.md" CHANGELOG.md
           sed -i -e "s/%%VERSION%%/${{ inputs.version }}/g" CHANGELOG.md
+          sed -i "8a ${{ join(fromJson(steps.notes.outputs.release-sections).release-notes, '\n') }}\n" CHANGELOG.md
           make generate-manifests
 
       - name: Create Pull Request