Add move/copy/delete methods on Asset

[jsignell]

Related Issue(s):

• RFC: Add move/copy/delete operations for local assets #911

Description:

Add methods to Asset, Item, and Collection to support moving/copying/deleting assets and their referenced data files.

PR Checklist:

• pre-commit hooks pass locally
• Tests pass (run scripts/test)
• 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

Patch coverage: 100.00% and project coverage change: +0.07 🎉

Comparison is base (579a644) 91.99% compared to head (6cd47f7) 92.06%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1158      +/-   ##
==========================================
+ Coverage   91.99%   92.06%   +0.07%     
==========================================
  Files          49       49              
  Lines        6611     6645      +34     
  Branches      978      980       +2     
==========================================
+ Hits         6082     6118      +36     
+ Misses        356      355       -1     
+ Partials      173      172       -1     

Impacted Files	Coverage Δ
pystac/asset.py	97.02% <100.00%> (+3.52%)	⬆️
pystac/collection.py	96.19% <100.00%> (+0.07%)	⬆️
pystac/item.py	93.24% <100.00%> (+0.15%)	⬆️

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[gadomski]

LGTM, just needs some doc fixes. The informative error messages and docs are 🤌