Type hint of specify_shape does not allow for None in shape

[sudarsan2k5]

fixes #1164
Updated specify_shape type hint , allowed None in shape

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[rlouf]

Thank you for opening a PR. It looks like you need to format your code using pre-commit.

[brandonwillard]

I just updated the formatting; this should be good to merge now. Thanks @sudarsan2k5!

[codecov]

Codecov Report

Merging #1313 (dff0aca) into main (a7ef6db) will increase coverage by 0.00%.
The diff coverage is 100.00%.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1313   +/-   ##
=======================================
  Coverage   74.22%   74.22%           
=======================================
  Files         174      174           
  Lines       48731    48732    +1     
  Branches    10367    10367           
=======================================
+ Hits        36170    36171    +1     
  Misses      10273    10273           
  Partials     2288     2288           

Impacted Files	Coverage Δ
aesara/tensor/shape.py	91.74% <100.00%> (+0.01%)	⬆️