Move ulimit check to install phase and switch user to reflect changes to the config

[dreambeyondorange]

Until now ulimit -Sn was used in the config step to confirm the changes in the install step are reflected in the running OS. This is no longer working in Ubuntu 22 because for whatever reason, the session that is created for Ubuntu 22 doesn't have the changes reflected, even though the files are in place. After launching an instance from the AMI however, the changes are there. To improve this test, we need to move it to the install step and check it immediately by switching users and forcing the loading of the limits.

Tests

• Tested with kitchen test suites using the install_users controls
• tested platform-install users for all OSes

Checklist

• Make sure you are pointing to the right branch and add a label in the PR title (i.e. 2.x vs 3.x)
• Check all commits' messages are clear, describing what and why vs how.
• Make sure to have added unit tests or integration tests to cover the new/modified code.
• Check if documentation is impacted by this change.

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[codecov]

Codecov Report

Merging #2393 (e56f02f) into release-3.7 (6881d0f) will not change coverage.
The diff coverage is n/a.

@@             Coverage Diff              @@
##           release-3.7    #2393   +/-   ##
============================================
  Coverage        70.34%   70.34%           
============================================
  Files               13       13           
  Lines             1851     1851           
============================================
  Hits              1302     1302           
  Misses             549      549           

Flag	Coverage Δ
unittests	70.34% <ø> (ø)

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