Bump SQLAlchemy to 2.0

[cloudsupper]

A lot of warnings for basically the same thing: use _mapping for dictionary interface to Row.

[cloudsupper]

mypy is a bit dumb

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 86.95652% with 3 lines in your changes missing coverage. Please review.

Project coverage is 63.58%. Comparing base (8675745) to head (f5d22c6). Report is 14 commits behind head on main.

Files with missing lines	Patch %	Lines
cashu/core/db.py	50.00%	3 Missing :warning:

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HEAD has 3 uploads less than BASE

Flag	BASE (8675745)	HEAD (f5d22c6)
	9	6

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #626      +/-   ##
==========================================
- Coverage   69.02%   63.58%   -5.44%     
==========================================
  Files          92       98       +6     
  Lines        8674    10565    +1891     
==========================================
+ Hits         5987     6718     +731     
- Misses       2687     3847    +1160     

Flag	Coverage Δ
	63.58% <86.95%> (?)

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[callebtc]

mypy is a bit dumb