Add a hidden `--force` flag for `rsconnect content build rm`

[dbkegley]

It is possible for a locally tracked content build to become out-of-sync with the state of the content items on the connect server. When this happens, we should provide an escape hatch for customers to cleanup their local state file without having to modify the json file directly.

https://github.com/posit-dev/rsconnect-python/commit/f33f14ba9b65a9e1bcea7ba179ee863738312e15