Tune component update configuration

- Include link to changelog of component in commit and PR message
- Label pull request automatically with `area/build`
- Enable sign-off of commits to free us from manual labour

Signed-off-by: Hidde Beydals <hello@hidde.co>

.github/workflows/update.yml

@@ -32,7 +32,7 @@ jobs:
                 go mod edit -require="github.com/fluxcd/$1/api@${RELEASE_VERSION}"
               fi
 
-              PR_BODY="$PR_BODY- $1 to ${RELEASE_VERSION}%0A"
+              PR_BODY="$PR_BODY- $1 to [${RELEASE_VERSION}](https://github.com/fluxcd/$1/blob/${RELEASE_VERSION}/CHANGELOG.md)%0A"
             fi
           }
 
@@ -51,7 +51,7 @@ jobs:
             # diff change
             git diff
 
-            # export PR_BODY for PR
+            # export PR_BODY for PR and commit
             echo "::set-output name=pr_body::$PR_BODY"
           }
 
@@ -60,19 +60,22 @@ jobs:
         uses: peter-evans/create-pull-request@v3
         with:
             token: ${{ secrets.BOT_GITHUB_TOKEN }}
-            commit-message: Update toolkit components
+            commit-message: |
+              Update toolkit components
+
+              ${{ steps.update.outputs.pr_body }}
             committer: GitHub <noreply@github.com>
             author: fluxcdbot <fluxcdbot@users.noreply.github.com>
+            signoff: true
+            branch: update-components
             title: Update toolkit components
             body: |
               ${{ steps.update.outputs.pr_body }}
-
-              Auto-generated by [create-pull-request][1]
-
-              [1]: https://github.com/peter-evans/create-pull-request
-            branch: update-components
+            labels: |
+              area/build
             reviewers: ${{ secrets.ASSIGNEES }}
 
       - name: Check output
         run: |
           echo "Pull Request Number - ${{ steps.cpr.outputs.pull-request-number }}"
+          echo "Pull Request URL - ${{ steps.cpr.outputs.pull-request-url }}"