Added moments for gumbel, triangular and logitnormal distributions for issue #5078

[sagartomar]

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[codecov]

Codecov Report

Merging #5180 (7816c73) into main (8d1708a) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main    #5180   +/-   ##
=======================================
  Coverage   78.05%   78.06%           
=======================================
  Files          88       88           
  Lines       14146    14161   +15     
=======================================
+ Hits        11042    11055   +13     
- Misses       3104     3106    +2     

Impacted Files	Coverage Δ
pymc/distributions/continuous.py	96.44% <100.00%> (+0.06%)	⬆️
pymc/data.py	79.55% <0.00%> (-0.45%)	⬇️
pymc/sampling.py	86.68% <0.00%> (-0.13%)	⬇️

[ricardoV94]

Looks great! Just need to fix the pre-commit formatting complaints

[ricardoV94]

Failing test seems related to know issues about MAP and not this PR. Merged it!