Fix bug in local_div_switch_sink rewrite

[ricardoV94]

Introduced in 4f7d709

Apparently no test covered this condition :)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 82.10%. Comparing base (f2ad711) to head (11b8fd6).
Report is 2 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1080   +/-   ##
=======================================
  Coverage   82.10%   82.10%           
=======================================
  Files         183      183           
  Lines       47928    47930    +2     
  Branches     8632     8633    +1     
=======================================
+ Hits        39352    39354    +2     
  Misses       6410     6410           
  Partials     2166     2166           

Files with missing lines	Coverage Δ
pytensor/graph/basic.py	88.66% <100.00%> (ø)
pytensor/tensor/rewriting/math.py	89.84% <100.00%> (+0.01%)	⬆️