Best effort copying of run directory

[michalpristas]

What does this PR do?

This PR is using onErr hook provided by copy utility.
This onErr is raised whenever tool encounters an error, it's up to a caller to decide what to do with the error. In this PR we log error and return nil (swallowing the error) resulting in a copy process not being terminated.

onErr is a custom hook introuced in my own fork of the tool (hence replace in go.mod)
I also opened a PR with this hook (fully tested) in copy repo: otiai10/copy#101
Once they decide to merge this we can remove our replace.

The other option was to perform copying by ourselves but the tool also handles symlinks and other edge cases already.

Unit tests for open handles also present.

Why is it important?

Prevents upgrade to fail on copy.

Checklist

• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have made corresponding change to the default configuration files
• I have added tests that prove my fix is effective or that my feature works
• I have added an entry in ./changelog/fragments using the changelog tool
• I have added an integration test or an E2E test

Fixes: #2433

[elasticmachine]

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• Start Time: 2023-04-05T13:53:55.630+0000

• Duration: 19 min 36 sec

Test stats 🧪

Test	Results
Failed	0
Passed	5411
Skipped	23
Total	5434

💚 Flaky test report

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[elasticmachine]

🌐 Coverage report

Name	Metrics % (covered/total)	Diff
Packages	98.485% (65/66)	👍
Files	69.604% (158/227)	👍
Classes	68.736% (299/435)	👍
Methods	53.915% (909/1686)	👍
Lines	39.052% (10179/26065)	👍 0.023
Conditionals	100.0% (0/0)	💚

[ycombinator]

Maybe invoke this via a defer so it will get executed even if the require.Equal on the previous line fails?

[ycombinator]

LGTM (pending @cmacknz's review feedback).

[mergify]

This pull request is now in conflicts. Could you fix it? 🙏
To fixup this pull request, you can check out it locally. See documentation: https://help.github.com/articles/checking-out-pull-requests-locally/

git fetch upstream
git checkout -b fix/upgrade-run-err upstream/fix/upgrade-run-err
git merge upstream/main
git push upstream fix/upgrade-run-err