Allow updating custom version fields

[epage]

Motivations

Before cargo add, it was common to have a manifest snippet with a version in it. There are still other cases of versions and other relevant information appearing in repos, like citation files.

• Would you like to implement this feature? maybe

Solution

cargo-release has a "pre-release replacements" set of regexes (example)

Alternatives

Hooks for running external programs. This exists in cargo-release but I never use it because its hard to do these cross-platform

Additional context

[MarcoIeni]

This sounds good to me.
We can call this field replacements in the config file and we can apply these replacements in the release-plz update command (and also release-pr). No need to support the command line argument.
These options look good, except from the prerelease one which doesn't apply for release-plz.
PR welcome!

[ruben-arts]

I'm also looking for this feature, also for the CITATION.cff but also possibly other files.

Next to that I'm also interested in the hooks, e.g. for bumping documentation.

Big thumbs up from me! 👍