Migrate from ligo-segments to igwn-segments

[duncanmmacleod]

This MR migrates this project from using ligo-segments (which is not supported on new Python versions) with igwn-segments, a fork that is updated and builds on all supported Python versions.

This should have no practical impact on this project or any users.

Standard information about the request

This is a: dependency update

This change affects: the offline search, the live search, inference, PyGRB

This change changes: everything, but has no API change

This change: has appropriate unit tests, follows style guidelines (See e.g. PEP8), has been proposed using the contribution guidelines

This change will: do nothing

Motivation

The ligo-segments project has not been maintained to the point where it doesn't compile for Python 3.12 with new compilers, or for Python 3.13 for any compiler (on all platforms). igwn-segments is a fork that fixes all of the build issues with no API changes.

Contents

All references to ligo-segments and its objects are replaced by the equivalent references to igwn-segments.

Links to any issues or associated PRs

Testing performed

Additional notes

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

[titodalcanton]

Long but trivial change, I only have a minor request above.

I would also like @spxiwh and @pannarale to acknowledge this before merging.

[spxiwh]

Acknowledged as requested!

[pannarale]

Looks like the from igwn_segments import infinity is unused in bin/all_sky_search/pycbc_sngls_findtrigs.
Other than that I have no more comments. Thanks, @duncanmmacleod.

[pannarale]

As a side note, there are other unused imports in this specific script: h5py, pycbc.conversions as conv, trigger_fits imported from pycbc.events as trfits, and indices_outside_times imported from pycbc.events.veto.

[spxiwh]

@GarethCabournDavies Please see the comments @pannarale makes here, which are unrelated to this PR, but might be worth addressing separately.