Duplicate capture group name

[tamusil-cen55253]

We want to use ${branch?} as mentioned here https://github.com/googleapis/release-please/blob/main/docs/customizing.md#pull-request-title

Steps to reproduce

1. Customize "pull-request-title-pattern": "chore${scope}: release${component} ${version} from ${branch}", inside release-please-config.json
2. Run release please

You will get error like Invalid regular expression: /^chore(\\((?<branch>[\\w-./]+)\\))?: release ?(?<component>@?[\\w-./]*)? v?(?<version>[0-9].*) from (?<branch>[\\w-./]+)?$/: Duplicate capture group name