Allow auto-bumping of version when doing assemble

[fsuits]

Issue description / feature objectives

Currently we only allow setting the version as a string, with no checks on the string contents. There is need for automatic bumping of the version when changes are made to a document. Create the following new options: --bump-major-version -bjv --bump-minor-version -bnv --bump-patch-version -bpv A github action would need to know what kind of bump is needed and specify the correct level to bump, but details of the use case are needed here.

Caveats / Assumptions

We need to establish the use case for bumping versions and decide if the logic needs to be within trestle based on changes to the document, or can it be known based on the label in the pull request, as in normal semantic versioning. We also need to select a module to perform the version bumping. We should error if the version string is not compatible with the semantic convention.

Completion Criteria