Provenance endpoint and test bug fixes

[munrojm]

Thie PR contains:

• Initial commit of new provenance endpoint
• Bug fixes for some endpoint client tests
• get_materials_id_references added to MPRester

[codecov-commenter]

Codecov Report

Merging #346 (fbda0b8) into main (1047518) will increase coverage by 0.07%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #346      +/-   ##
==========================================
+ Coverage   93.10%   93.17%   +0.07%     
==========================================
  Files          59       60       +1     
  Lines        1943     1950       +7     
==========================================
+ Hits         1809     1817       +8     
+ Misses        134      133       -1     

Impacted Files	Coverage Δ
src/mp_api/matproj.py	98.38% <100.00%> (+0.80%)	⬆️
src/mp_api/routes/__init__.py	100.00% <100.00%> (ø)
src/mp_api/routes/provenance/client.py	100.00% <100.00%> (ø)
src/mp_api/routes/xas/client.py	80.95% <100.00%> (ø)

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