add possibility to override/extend version name and version separator

[skarzi]

Hi 👋

thanks for super GitHub action!

It would be great to have the possibility to replace (or extend) regexp of the separator used to separate version name (e.g REVIEWDOG_VERSION) and version (e.g. 0.1.0) - currently it's equal to (=|:?\s+) - which is probably fine for most cases, but, for instance, not when you want to update the value in the file where each line is formatted like plugin-name:1.2.3.

It can be done by some action's input e.g. separator_regexp: ':\s*'.
Such a configuration option will make depup action much more versatile

[rickstaa]

@skarzi I think pull request #21 adds this feature.

[skarzi]

yes, currently a majority of cases are handled properly!