chore: skip typing checkers in "_version.py"

[mr-cal]

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Ignore _version.py (similar to canonical/craft-application#82).

Hidden and pycache files must to be explicitly excluded once the exclude keyword is used. (see the pyright documentation)

[codecov]

Codecov Report

Merging #404 (d1a37ac) into main (91fc208) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #404   +/-   ##
=======================================
  Coverage   98.98%   98.98%           
=======================================
  Files          57       57           
  Lines        4454     4454           
=======================================
  Hits         4409     4409           
  Misses         45       45