Improves diagnostic information for 'Any' type

[jspaezp]

Discussed here:
#100

[codecov-commenter]

Codecov Report

Attention: 2 lines in your changes are missing coverage. Please review.

Comparison is base (c85de71) 91.12% compared to head (e8c4300) 90.27%.

Files	Patch %	Lines
src/pydantic_avro/base.py	0.00%	2 Missing ⚠️

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Additional details and impacted files

@@            Coverage Diff             @@
##             main     #101      +/-   ##
==========================================
- Coverage   91.12%   90.27%   -0.85%     
==========================================
  Files           2        2              
  Lines         214      216       +2     
==========================================
  Hits          195      195              
- Misses         19       21       +2     

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[DaanRademaker]

Thanks for the pull request! I will approve and merge as soon as I can. I se that some the tests in our pipeline are failing. (Failure to install poetry on 3.7 it seems). I will first need to fix this before I can get this pull request through.

[DaanRademaker]

Thanks for your contribution. Will merge the changes.