feat: add sender rule for pipelines

[ecrupper]

This will allow teams to specify a sender for a specific step:

- name: no robots please
   image: alpine
   ruleset:
     unless:
       sender: "Mr. Robot"
   commands:
     - run something

[codecov]

Codecov Report

Attention: Patch coverage is 90.62500% with 3 lines in your changes missing coverage. Please review.

Project coverage is 56.87%. Comparing base (a2b0d91) to head (90693cf).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
compiler/types/pipeline/ruleset.go	57.14%	2 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1206      +/-   ##
==========================================
+ Coverage   56.85%   56.87%   +0.01%     
==========================================
  Files         599      599              
  Lines       32834    32856      +22     
==========================================
+ Hits        18668    18687      +19     
- Misses      13533    13535       +2     
- Partials      633      634       +1     

Files with missing lines	Coverage Δ
api/pipeline/compile.go	62.19% <100.00%> (+6.48%)	⬆️
compiler/native/compile.go	70.37% <100.00%> (+0.07%)	⬆️
compiler/types/yaml/ruleset.go	100.00% <100.00%> (ø)
compiler/types/pipeline/ruleset.go	76.76% <57.14%> (-1.35%)	⬇️

[KellyMerrick]

lgtm