Configure Dependabot to group related dependency updates into a single pull request using groups in dependabot.yml

Steps

1. In .github/dependabot.yml, under the relevant package-ecosystem update entry, add a groups: key with one or more named groups.
2. For each group, constrain membership with dependency-type (development or production), patterns (wildcard strings matching dependency names), exclude-patterns, and/or update-type (e.g. minor and patch together).
3. Commit the file and let Dependabot's next scheduled run (or a manually triggered check) evaluate it; matching dependencies with updates available are bundled into one PR titled after the group name instead of one PR each.
4. Adjust patterns/exclude-patterns iteratively based on the actual PRs Dependabot opens, since overly broad patterns can pull unrelated packages into a group.
5. Combine grouping with open-pull-requests-limit and schedule settings to control how many grouped and ungrouped PRs are open at once.