refactor: Use PEP-604 annotations for union types

[gfieni]

PEP 604 – Allow writing union types as X | Y

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 67.92%. Comparing base (81cdaff) to head (0af9803).
Report is 3 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #537      +/-   ##
==========================================
- Coverage   67.95%   67.92%   -0.04%     
==========================================
  Files          71       71              
  Lines        2968     2965       -3     
==========================================
- Hits         2017     2014       -3     
  Misses        951      951              

Files with missing lines	Coverage Δ
src/powerapi/dispatch_rule/dispatch_rule.py	83.33% <100.00%> (-2.39%)	⬇️
...werapi/processor/pre/k8s/metadata_cache_manager.py	100.00% <100.00%> (ø)
src/powerapi/processor/pre/k8s/monitor_agent.py	55.78% <100.00%> (-0.47%)	⬇️