Add convenience method for accessing pystac_client

[jsignell]

Related Issue(s):

• Closes #1334

Description:

from pystac.client import Client

PR Checklist:

• [x] pre-commit hooks pass locally
• [x] Tests pass (run scripts/test)
• [ ] Documentation has been updated to reflect changes, if applicable
• [x] 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[bot]]

Codecov Report

Attention: Patch coverage is 38.46154% with 8 lines in your changes missing coverage. Please review.

Project coverage is 91.19%. Comparing base (a88906b) to head (1ea5ae6). Report is 41 commits behind head on main.

Files with missing lines	Patch %	Lines
pystac/client.py	38.46%	7 Missing and 1 partial :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1365      +/-   ##
==========================================
- Coverage   91.28%   91.19%   -0.10%     
==========================================
  Files          51       52       +1     
  Lines        7221     7234      +13     
  Branches     1018     1019       +1     
==========================================
+ Hits         6592     6597       +5     
- Misses        450      457       +7     
- Partials      179      180       +1     

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[jsignell]

I can either ignore this file in coverage or I can try to figure out a test for the the case where pystac_client is not importable.

[jsignell]

All right! I ended up ignoring mypy. Mypy passes if pystac_client is installed, but it didn't seem worth it to try to mock out a stub or something. Another option I suppose would be to add pystac_client as a test requirement, but that might not be desirable.

[jsignell]

I just added a smidge of docs:

[alexgleith]

Love it! Thank you 🙏