Cherry-pick #24343 to 7.12: Fix windows installer during enroll

[michalpristas]

Cherry-pick of PR #24343 to 7.21 branch. Original message:

What does this PR do?

after #24253 issue still occurred on some systems.
the problem really is with rename and sync after unzip which is skipped in case ctx is cancelled.
my first option was to make agent rename rootDir even if zip is not fully unpacked and sync directories all rootDir, installDir and temp directories.
this complicated code to the form I did not like, so many conditions there. but it was working 5/5

i went with a code-cleaner way (especially with change in mind @blakerouse suggested that we should remove it before start) and i let unzip finish, rename rootDir to correct tmp install path, sync paths and then let awaitable installer wait for whole installation to finish. we lose tiny amount of time, but cleaner code is worth small perf impact especially in this edge case scenario.

Why is it important?

Fixes #24317

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.next.asciidoc or CHANGELOG-developer.next.asciidoc.

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Pinging @elastic/ingest-management (Team:Ingest Management)

[blakerouse]

Backport looks good.

[elasticmachine]

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• Build Cause: Pull request #24389 opened

• Start Time: 2021-03-05T15:01:44.876+0000

• Duration: 114 min 33 sec

• Commit: 5001eaf

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Failed	0
Passed	6500
Skipped	24
Total	6524

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Test	Results
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Passed	6500
Skipped	24
Total	6524