* Upgrade codespell to v2.4.0
It is a lastet verison, and is needed so that I can use the inline
ignore support in a future commit.
After updating tests/pyproject.toml I ran the following commands:
```
cd tests
poetry lock --no-update
poetry install
```
I also fixed a spelling error in man/git-summary.md, which was not
caught by the old version of codespell. After updating the file I also
updated the related files by running the following commands:
```
cd man
make -C .. man/git-summary.{1,html}
```
* add git-wip and git-unwip
Updated/re-built the documentation with:
```
cd man
make -C .. man/git-unwip.{1,html}
make -C .. man/git-wip.{1,html}
make -C .. man/git-extras.{1,html}
```
