refactor: share UpdateFromEnv logic

[ChristopherHX]

No public interface has been changed.

TODO

• Add tests for bugs of the old docker_run impl.
• Add tests for GITHUB_OUTPUT / GITHUB_STATE

[github-actions]

🦙 MegaLinter status: ✅ SUCCESS

Descriptor	Linter	Files	Fixed	Errors	Elapsed time
✅ EDITORCONFIG	editorconfig-checker	4		0	0.03s
✅ REPOSITORY	gitleaks	yes		no	2.91s
✅ REPOSITORY	git_diff	yes		no	0.0s
✅ REPOSITORY	secretlint	yes		no	1.22s

See errors details in artifact MegaLinter reports on CI Job page
Set VALIDATE_ALL_CODEBASE: true in mega-linter.yml to validate all sources, not only the diff

MegaLinter is graciously provided by

[codecov]

Codecov Report

Merging #1457 (fa8753e) into master (4f8da0a) will increase coverage by 3.53%.
The diff coverage is 67.15%.

@@            Coverage Diff             @@
##           master    #1457      +/-   ##
==========================================
+ Coverage   57.50%   61.04%   +3.53%     
==========================================
  Files          32       45      +13     
  Lines        4594     6955    +2361     
==========================================
+ Hits         2642     4246    +1604     
- Misses       1729     2408     +679     
- Partials      223      301      +78     

Impacted Files	Coverage Δ
pkg/common/file.go	0.00% <0.00%> (ø)
pkg/container/docker_logger.go	52.08% <ø> (ø)
pkg/container/host_environment.go	0.00% <0.00%> (ø)
pkg/container/parse_env_file.go	0.00% <0.00%> (ø)
pkg/container/util.go	0.00% <0.00%> (ø)
pkg/model/action.go	0.00% <0.00%> (ø)
pkg/model/step_result.go	0.00% <ø> (ø)
pkg/container/docker_run.go	13.58% <11.48%> (+8.04%)	⬆️
pkg/model/workflow.go	45.65% <23.58%> (-5.26%)	⬇️
...ontainer/linux_container_environment_extensions.go	24.32% <24.32%> (ø)
... and 38 more

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more