Enable gci correctly

[shuheiktgw]

What does this PR do?

Even though the gci configuration exists in .golangci.toml, GCI itself has been disabled. I believe it would be better if we could enforce some rules on import statements and automatically lint and format them.

Thanks for your review!

Motivation

Lint & sort the import statements automatically.

Checklist

• PR has at least one valid label: bug, enhancement, refactoring, documentation, tooling, and/or dependencies
• PR has a milestone or the qa/skip-qa label

[shuheiktgw]

I don't have permission to attach labels so could anybody help me attach appropriate labels to the PR?

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 49.32%. Comparing base (0300de3) to head (80e9a4c).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1671   +/-   ##
=======================================
  Coverage   49.32%   49.32%           
=======================================
  Files         218      218           
  Lines       21171    21171           
=======================================
  Hits        10442    10442           
  Misses      10184    10184           
  Partials      545      545           

Flag	Coverage Δ
unittests	49.32% <ø> (ø)

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

Files with missing lines	Coverage Δ
cmd/check-operator/main.go	0.00% <ø> (ø)
cmd/check-operator/upgrade/upgrade.go	0.00% <ø> (ø)
cmd/helpers/main.go	0.00% <ø> (ø)
cmd/helpers/secrets/secrets.go	0.00% <ø> (ø)
cmd/kubectl-datadog/agent/agent/agent.go	0.00% <ø> (ø)
cmd/kubectl-datadog/agent/check/check.go	9.22% <ø> (ø)
cmd/kubectl-datadog/agent/find/find.go	0.00% <ø> (ø)
cmd/kubectl-datadog/agent/upgrade/upgrade.go	12.64% <ø> (ø)
...-datadog/clusteragent/clusteragent/clusteragent.go	0.00% <ø> (ø)
cmd/kubectl-datadog/clusteragent/leader/leader.go	0.00% <ø> (ø)
... and 122 more

---

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[celenechang]

thanks for the change, just left one comment

[celenechang]

successfully built locally

[gabedos]

Looks good for container-platform files

[jennchenn]

lgtm for container-integrations files (only changes were import re-orders)