[release-1.9] feat: enabled s2i for python (#1562)

[lance]

This is a cherry pick of #1562 to enable s2i builds for Python in 1.9.x releases.

/cc @matejvasek

/kind enhancement

[matejvasek]

/approve
/lgtm

[codecov]

Codecov Report

Base: 63.01% // Head: 60.82% // Decreases project coverage by -2.20% ⚠️

Coverage data is based on head (c746055) compared to base (5333945).
Patch has no changes to coverable lines.

❗ Current head c746055 differs from pull request most recent head ff0f592. Consider uploading reports for the commit ff0f592 to get more accurate results

Additional details and impacted files

@@               Coverage Diff               @@
##           release-1.9    #1579      +/-   ##
===============================================
- Coverage        63.01%   60.82%   -2.20%     
===============================================
  Files               74       74              
  Lines            10764    10070     -694     
===============================================
- Hits              6783     6125     -658     
+ Misses            3422     3388      -34     
+ Partials           559      557       -2     

Flag	Coverage Δ
integration-tests	49.95% <ø> (-3.29%)	⬇️
unit-tests-macos-latest	49.98% <ø> (?)
unit-tests-ubuntu-latest	51.50% <ø> (?)
unit-tests-windows-latest	50.00% <ø> (?)

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

Impacted Files	Coverage Δ
s2i/builder.go	61.33% <ø> (ø)
docker/zz_close_guarding_client_generated.go
docker/docker_client_nonlinux.go	0.00% <0.00%> (ø)
knative/deployer.go	62.13% <0.00%> (+0.49%)	⬆️
client.go	62.57% <0.00%> (+0.61%)	⬆️
docker/creds/credentials.go	73.06% <0.00%> (+1.34%)	⬆️
docker/docker_client.go	84.87% <0.00%> (+23.52%)	⬆️

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[matejvasek]

/approve
/lgtm

[knative-prow]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: lance, matejvasek

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