Post release 3.8.0 reset

* force remapping to be calculated from iac, ja array
* add 0 digit padding to file names
* update UnstructuredGrid, add cell2d input parameter and property method
* add clean_iverts() to UnstructuredGrid to remove duplicated vertex and invert information
* update testing for new features

Add an unquantified wildcard to the pattern in cliff.toml so commit messages like 'updates(...): ...' are included in the refactor group in the auto-generated changelog at release time

…j are not present (#2294)

* fix for "k", "node" output present with mp7 pathline and timeseries

* fix(modelgrid): add more support for mf6 surface water models

* ruff

Commit messages were omitted from the generated changelog if they had any leading whitespace. Fix it.

Explicitly add files to commit after updating the version number and generating the changelog. Previously we used 'git add -A'. As of git-cliff-action@v4 this includes the git-cliff binary and related content which is apparently installed to the working directory.

…ate changelog