Add space_group_symmetry_operations_xyz and sub-definition for sym ops

[ml-evs]

Currently uses the proposed ECMA regexp at Materials-Consortia#488

Schemas will fail to generate unless we add pattern Materials-Consortia#460 (comment) in Materials-Consortia#460

[ml-evs]

This is currently blocked by Materials-Consortia#486

[rartino]

@ml-evs So Materials-Consortia#486 is merged, so that part is fine.

I know things have gotten a bit messy with the two PRs, and perhaps I should just merge Materials-Consortia#460 into this one and close Materials-Consortia#460, now that the two are in sync. But, in any case, this PR (as in Materials-Consortia#445) needs the meta-schema updated for the pattern field. But, ok, I'll merge this, and can add that.

[rartino]

@ml-evs But, eh, wait, how completely does this PR cover Materials-Consortia#464? I thought we at least modified the definition of some of the other symmetry fields, but maybe we didn't(?)

[ml-evs]

Hi @rartino, indeed this needed to be updated with the results of that PR (and also to include the other fields). I'll try to get around to that soon.

[rartino]

@ml-evs The changes relating to the other fields seemed quite minor, so in an effort to get things ready while I have time, I've added/modified them myself. I've also modified the meta schema for property definitions to allow the 'pattern' field for strings (but when/if Materials-Consortia#490 is merged, we should adjust the description). However, I though it to be fair to leave it to you add the fancy regex you worked out. Note: the place to add it is now in: schemas/src/defs/v1.2/properties/optimade/common/space_group_symmetry_operation_xyz.yaml which is the definition of a single symop, which is inherited by space_group_symmetry_operations_xyz.yaml.