ICSHWI-9009 Added force flag to conda_env state:absent

In https://jira.esss.lu.se/browse/INFRA-4846 it was reported that creation of conda environments failed because of an I/O error although some directories were created. That failed environment cannot be deleted with conda because conda returns a DirectoryNotACondaEnvironmentError. This MR addresses this removal issue.

Can be used to forcibly remove partial conda environments. One use case is when conda itself throws an exception during environment creation. A simple conda remove will not work because conda thinks that the directory you specified is not a conda environment. In that case we can just delete the directory.

Dear @andersharrisson could you please take a look at it?

Thanks!