[supervisor] Correctly reap child processes

[csweichel]

fixes #5091

by reaping all child processes, respecting wait interruptions and not blocking the SIGCHILD handler.

[codecov]

Codecov Report

Merging #5100 (b9ca184) into main (2e5f169) will increase coverage by 36.10%.
The diff coverage is 0.00%.

@@            Coverage Diff            @@
##           main    #5100       +/-   ##
=========================================
+ Coverage      0   36.10%   +36.10%     
=========================================
  Files         0       16       +16     
  Lines         0     4080     +4080     
=========================================
+ Hits          0     1473     +1473     
- Misses        0     2483     +2483     
- Partials      0      124      +124     

Flag	Coverage Δ
components-supervisor-app	36.10% <0.00%> (?)

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

Impacted Files	Coverage Δ
components/supervisor/pkg/supervisor/supervisor.go	0.00% <0.00%> (ø)
components/supervisor/pkg/ports/served-ports.go	76.00% <0.00%> (ø)
components/supervisor/pkg/supervisor/services.go	25.50% <0.00%> (ø)
components/supervisor/pkg/terminal/terminal.go	63.27% <0.00%> (ø)
components/supervisor/pkg/supervisor/tasks.go	55.22% <0.00%> (ø)
components/supervisor/pkg/ports/ports.go	60.21% <0.00%> (ø)
...mponents/supervisor/pkg/supervisor/notification.go	83.95% <0.00%> (ø)
components/supervisor/pkg/ports/ports-config.go	79.85% <0.00%> (ø)
components/supervisor/pkg/ports/tunnel.go	63.63% <0.00%> (ø)
components/supervisor/pkg/ports/exposed-ports.go	0.00% <0.00%> (ø)
... and 7 more

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[akosyakov]

/werft run

👍 started the job as gitpod-build-cw-reaper.1

[akosyakov]

/lgtm

I cannot see defunct processes anymore.

[roboquat]

LGTM label has been added.

Git tree hash: 82710b2682835f134a3d886f0a52ccbe88bee696

[roboquat]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: akosyakov

Associated issue: #5091

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• components/supervisor/OWNERS [akosyakov]

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