[Feature] Make branch name and commit message configurable

[lisachenko]

Is your feature request related to a problem? Please describe.
We are adopting Change Management policy, which requires Conventional Branch names and requires to have a Jira ticket identifier in the branch name to link all changes to relevant tickets. Unfortunately, this can not be fine-tuned or configured, like in Crowdin action

Describe the solution you'd like
I would like to propose to have configuration of branch name and commit message, which can be fine-tuned according to existing rules, similarly to the Crowdin action configuration: https://github.com/crowdin/github-action?tab=readme-ov-file#git-and-pull-request-options

Option	Description
commit_message	The commit message for the pushed changes
branch_name	The name of the git branch that Release-please will create when pushing new release version changes

Describe alternatives you've considered
Alternatively, I can put "release-please--branches--main" into the exclude list for Conventional Branches ruleset, but still I don't like that branch name always the same and looks weird in the log messages. Another alternative to branch_name is to define a prefix for the branch: branch_prefix: release/. Then we can create a routine ticket TASK-1234 for release automation and together with commit message chore(release): TASK-1234: Release version v1.2.3 it will respect Conventional Branch name, Conventional Commit message specifications and also will satisfy stricter ITGC Change Management rulesets or ISO 27001:2022 Annex A Control 8.32.
Release-please can take then the branch_prefix and use it to form the full release branch name like this release/v1.2.3 (see #1168)

Additional context
Would be nice to configure the scope for commit and make it non-standard: chore(main): xxxx as we don't have a scope, equal to main

Thanks in advance!