Move to igwn-ligolw

[titodalcanton]

Move from python-ligo-lw to the recently released and more modern igwn-ligolw.

Standard information about the request

This is a depencency change.
This change should have no impact on any functionality or result.
This change will drop the dependency on python-ligo-lw and introduce a depencency on igwn-ligolw.

Motivation

igwn-ligolw is more actively maintained and supports modern Python versions and more architectures than python-ligo-lw.

Contents

Mainly replacing imports, but the transition from python-ligo-lw 1.8.3 to igwn-ligolw 2.0.0 has the side effect of introducing a few breaking changes which never made it to a python-ligo-lw release yet, as well as a couple deprecation warnings, so those are handled as well. We can also further simplify tox.ini, consistently with #4857.

Links to any issues or associated PRs

This is essentially a counterpart to #4999. Improves #4857.

Testing performed

Ran tox and a few of the tests manually on a local machine, but I am relying on the CI for now.

Additional notes

I am not sure I want to push this to production codes yet, at least not before more significant testing is done with workflows and GraceDB interactions. In particular, I think we should create a release branch for PyGRB's O4a analysis before merging this (@pannarale). So I am applying a "on hold" label.

• The author of this pull request confirms they will adhere to the code of conduct

[titodalcanton]

Started to do some more thorough tests. Noting down a few more deprecations to address:

UserWarning: igwn_ligolw.utils.process.register_to_xmldoc() is deprecated.  use igwn_ligolw.ligolw.Document.register_process() instead.
UserWarning: igwn_ligolw.lsctables.New() is deprecated.  use igwn_ligolw.Table.new() instead.
UserWarning: igwn_ligolw.lsctables.use_in() is deprecated.  simply importing the lsctables module automatically enables the custom table support features it provides.

Edit: these have been addressed now.

[titodalcanton]

I made a test run of the PyCBC Live example uploading to GraceDB test and I do not see particular issues, so I am gaining confidence about this.