Adding setup python

[gillettmoj]

Purpose

Adds setup python to workflow

Fixes UML-3679

Approach

Explain how your code addresses the purpose of the change

Learning

Any tips and tricks, blog posts or tools which helped you. Plus anything notable you've discovered about the Use a Lasting Power of Attorney service

Checklist

• I have performed a self-review of my own code
• I have added relevant logging with appropriate levels to my code
• New event_codes have been documented on the wiki page
• I have updated documentation (Confluence/GitHub wiki/tech debt doc) where relevant
• I have added tests to prove my work
• I have added welsh translation tags and updated translation files
• I have run an accessibility tool on any pages I have made changes to and fixed any issues found
• I have notified the Interaction Designer of any content changes so that appropriate screenshots/flow diagram changes can be made
• The product team have tested these changes

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 91.64%. Comparing base (f00760a) to head (ca9cbd9).
Report is 94 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #2877      +/-   ##
============================================
+ Coverage     91.25%   91.64%   +0.39%     
- Complexity     1504     1624     +120     
============================================
  Files           309      345      +36     
  Lines          6393     6802     +409     
============================================
+ Hits           5834     6234     +400     
- Misses          542      551       +9     
  Partials         17       17              

Flag	Coverage Δ
use-an-lpa-admin	79.26% <ø> (ø)
use-an-lpa-api	97.64% <ø> (+0.27%)	⬆️
use-an-lpa-front	89.35% <ø> (-0.19%)	⬇️

see 2 files with indirect coverage changes