Add header processing abilities to certain Resource classes

[munrojm]

This PR allows the ReadOnlyResource to take in a HeaderProcessor object to manipulate header information for each request.

[codecov]

Codecov Report

Merging #569 (3e2a6a8) into main (b14a5b2) will increase coverage by 0.09%.
The diff coverage is 91.89%.

@@            Coverage Diff             @@
##             main     #569      +/-   ##
==========================================
+ Coverage   89.02%   89.11%   +0.09%     
==========================================
  Files          40       40              
  Lines        2743     2794      +51     
==========================================
+ Hits         2442     2490      +48     
- Misses        301      304       +3     

Impacted Files	Coverage Δ
src/maggma/api/resource/read_resource.py	96.38% <88.23%> (-2.30%)	⬇️
src/maggma/api/resource/aggregation.py	92.85% <90.00%> (-1.59%)	⬇️
src/maggma/api/resource/__init__.py	100.00% <100.00%> (ø)
src/maggma/api/resource/core.py	80.00% <100.00%> (+1.42%)	⬆️
src/maggma/api/resource/post_resource.py	97.82% <100.00%> (+0.04%)	⬆️
src/maggma/api/resource/submission.py	87.50% <100.00%> (+0.24%)	⬆️
src/maggma/api/resource/utils.py	100.00% <100.00%> (ø)
src/maggma/core/drone.py	92.42% <0.00%> (ø)
src/maggma/cli/distributed.py	100.00% <0.00%> (ø)
src/maggma/stores/gridfs.py	94.35% <0.00%> (+0.09%)	⬆️
... and 2 more

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