codecov: add target and threshold

[eguzki]

What

Added Codecov Status Check target and threshold

target is the minimum coverage ratio that the commit must meet to be considered a success.

threshold allows the coverage to drop by X%, and posting a success status.

❯ cat .github/codecov.yaml | curl --data-binary @- https://codecov.io/validate
Valid!

[codecov-commenter]

⚠️ Please install the to ensure uploads and comments are reliably processed by Codecov.

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 52.24%. Comparing base (48f950c) to head (2cc9caf).
Report is 173 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #104      +/-   ##
==========================================
- Coverage   53.97%   52.24%   -1.74%     
==========================================
  Files          12       12              
  Lines         867      867              
==========================================
- Hits          468      453      -15     
- Misses        363      374      +11     
- Partials       36       40       +4     

Flag	Coverage Δ
integration	53.69% <ø> (-4.83%)	⬇️
unit	51.43% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
api/v1alpha1 (u)	100.00% <ø> (ø)
pkg/helpers (u)	9.75% <ø> (ø)
pkg/log (u)	31.81% <ø> (ø)
pkg/reconcilers (u)	26.60% <ø> (ø)
pkg/limitador (u)	72.02% <ø> (ø)
controllers (i)	53.69% <ø> (-4.83%)	⬇️

see 2 files with indirect coverage changes

[KevFan]

Looks good to me 👍