Bump peter-evans/create-pull-request from 7 to 8 (#4287)

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/create-condalock-file.yml

@@ -73,7 +73,7 @@ jobs:
       # Automated PR
       # see https://github.com/marketplace/actions/create-pull-request
       - name: Create Automated PR if conda lock file has changed
-        uses: peter-evans/create-pull-request@v7
+        uses: peter-evans/create-pull-request@v8
         with:
           token: ${{ secrets.GITHUB_TOKEN }}
           commit-message: Updating Linux condalock file

.github/workflows/cron_esmvalbot_test.yml

@@ -30,7 +30,7 @@ jobs:
       # as comment in the PR
       # see https://github.com/marketplace/actions/create-pull-request
       - name: Create Auto PR
-        uses: peter-evans/create-pull-request@v7
+        uses: peter-evans/create-pull-request@v8
         with:
           token: ${{ secrets.GITHUB_TOKEN }}
           commit-message: empty message