Rename sgn to sign

[sudarsan2k5]

fixes #162

• Rename sgn with sign
• Deprecated sgn

Checklist

• Make sure that the pre-commit linting/style checks pass.
• Link relevant issues, preferably in nice commit messages.
• The commits correspond to relevant logical changes. Note that if they don't, we will rewrite/rebase/squash the git history before merging.
• Are the changes covered by tests and docstrings?

[twiecki]

@sudarsan2k5 Thanks! Note the conflicts, you need to rebase from main.

[sudarsan2k5]

by mistakenly converted to draft

[codecov-commenter]

Codecov Report

Merging #228 (0218c36) into main (63f8d6e) will not change coverage.
The diff coverage is 100.00%.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #228   +/-   ##
=======================================
  Coverage   80.43%   80.43%           
=======================================
  Files         170      170           
  Lines       45326    45326           
  Branches     9687     9687           
=======================================
  Hits        36457    36457           
  Misses       6643     6643           
  Partials     2226     2226           

Impacted Files	Coverage Δ
pytensor/compile/profiling.py	75.35% <ø> (ø)
pytensor/scalar/basic.py	79.77% <100.00%> (ø)
pytensor/sparse/basic.py	82.49% <100.00%> (ø)
pytensor/tensor/inplace.py	100.00% <100.00%> (ø)
pytensor/tensor/math.py	90.69% <100.00%> (ø)
pytensor/tensor/rewriting/math.py	86.03% <100.00%> (ø)
pytensor/tensor/subtensor.py	89.64% <100.00%> (ø)

[ricardoV94]

Do you mind adding a compatible sgn like this (and make it accessible from pytensor.tensor as before.

Suggested change

	def sgn(a):
	warnings.warn(
	"sgn is deprecated and will stop working in the future, use sign instead.",
	FutureWarning,
	)
	return sign(a)

[sudarsan2k5]

Hi @ricardoV94 I have implemented the suggested changes, could you please check if we need anything else in this PR?

[ricardoV94]

@sudarsan2k5 Sorry I just wanted to check locally the old import is still working. I'll do it tomorrow and merge after

[ricardoV94]

Thanks @sudarsan2k5, merged!