Analysis types in metamist.py not consistent with Metamist

Analysis types listed in `metamist.py` appear to be strictly enforcing a set of analysis types, but these are not consistent with the actual analysis types recorded in Metamist. This is due to being able to create any arbitrary analysis type via the swagger API.

https://github.com/populationgenomics/cpg-flow/blob/main/src/cpg_flow/metamist.py#L167
