feat(spy): warn if mock used with a missing attribute

[mcous]

This PR introduces a MissingSpecAttributeWarning that will be thrown if you try to use an attribute of a mock that does not exist on its spec. Closes #204.

In the next major version of Decoy, this warning will become an error.

[mcous]

Current dependencies on/for this PR:

• main
  • PR chore: upgrade docs dependencies and fix warnings #217
    • PR feat(spy): warn if mock used with a missing attribute #218 👈
      • PR refactor(warnings): rework MiscalledStubWarning checker for clarity #219

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[codecov]

Codecov Report

Merging #218 (34fb688) into main (d8c6923) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main     #218   +/-   ##
=======================================
  Coverage   98.36%   98.37%           
=======================================
  Files          19       19           
  Lines         736      739    +3     
  Branches       87       88    +1     
=======================================
+ Hits          724      727    +3     
  Misses         10       10           
  Partials        2        2           

Files Changed	Coverage Δ
decoy/spy_core.py	100.00% <100.00%> (ø)
decoy/warnings.py	100.00% <100.00%> (ø)