ci/request-reviews: Make wrong base branch message hashes more transp…

…arent

Also, fix the description of the text

ci/request-reviews/verify-base-branch.sh

@@ -90,8 +90,9 @@ for testBranch in "${devBranches[@]}"; do
         log -e "\e[33m"
         echo "The PR's base branch is set to $baseBranch, but $extraCommits commits from the $testBranch branch are included. Make sure you know the [right base branch for your changes](https://github.com/NixOS/nixpkgs/blob/master/CONTRIBUTING.md#branch-conventions), then:"
         echo "- If the changes should go to the $testBranch branch, [change the base branch](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/proposing-changes-to-your-work-with-pull-requests/changing-the-base-branch-of-a-pull-request) to $testBranch"
-        echo "- If the changes should go to the $baseBranch branch, rebase your PR onto the merge base with the $testBranch branch:"
-        echo "  \`\`\`"
+        echo "- If the changes should go to the $baseBranch branch, rebase your PR onto the merge base with the $baseBranch branch:"
+        echo "  \`\`\`bash"
+        echo "  # git rebase --onto \$(git merge-base upstream/$baseBranch HEAD) \$(git merge-base upstream/$testBranch HEAD)"
         echo "  git rebase --onto $prMergeBase $testMergeBase"
         echo "  git push --force-with-lease"
         echo "  \`\`\`"