Add MLM extension

[jonas-hurst]

Related Issue(s):

• fixes Add support for stac:mlm extension #1540

Description:
Adds the STAC:MLM extension: https://github.com/stac-extensions/mlm

PR Checklist:

• Pre-commit hooks pass (run pre-commit run --all-files)
• Tests pass (run pytest)
• Documentation has been updated to reflect changes, if applicable
• This PR maintains or improves overall codebase code coverage.
• Changes are added to the CHANGELOG. See the docs for information about adding to the changelog.

[codecov]

Codecov Report

Attention: Patch coverage is 99.48849% with 4 lines in your changes missing coverage. Please review.

Project coverage is 92.35%. Comparing base (e713adf) to head (477f5f9).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
pystac/extensions/mlm.py	99.47%	2 Missing and 2 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1542      +/-   ##
==========================================
+ Coverage   91.62%   92.35%   +0.73%     
==========================================
  Files          54       55       +1     
  Lines        7578     8360     +782     
  Branches      923      960      +37     
==========================================
+ Hits         6943     7721     +778     
- Misses        451      453       +2     
- Partials      184      186       +2     

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[gadomski]

Thanks for the contribution! Some minor tweaks requested, mostly spelling.

[fmigneault]

Thanks for the integration.
Let us know when the new version is released.
I will cross-reference it in the MLM repository (see stac-extensions/mlm#85).

[gadomski]

Will do! I'm going to try to squeeze in #1549 and then cut a v1.13

[gadomski]

• https://github.com/stac-utils/pystac/releases/tag/v1.13.0
• https://pypi.org/project/pystac/1.13.0/