chore: cleanup unused env variables in Makefile

[odubajDT]

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[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
0.1% Duplication

[codecov]

Codecov Report

Merging #1913 (e206ea5) into main (fa2b54d) will decrease coverage by 0.10%.
Report is 3 commits behind head on main.
The diff coverage is n/a.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1913      +/-   ##
==========================================
- Coverage   83.90%   83.81%   -0.10%     
==========================================
  Files         141      141              
  Lines        8588     8588              
==========================================
- Hits         7206     7198       -8     
- Misses       1126     1132       +6     
- Partials      256      258       +2     

see 4 files with indirect coverage changes

Flag	Coverage Δ
certificate-operator	68.55% <ø> (ø)
component-tests	58.25% <ø> (-1.10%)	⬇️
lifecycle-operator	84.92% <ø> (ø)
metrics-operator	85.37% <ø> (ø)
scheduler	32.12% <ø> (ø)

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