Preventing incorrect metrics to be sent on telemetry

[vrdmr]

Description

Issue #

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PR information

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• There are a small number of commits, each of which has an informative message. This means that previously merged commits do not appear in the history of the PR. For information on cleaning up the commits in your pull request, see this page.
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Quality of Code and Contribution Guidelines

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This change is 

[codecov]

Codecov Report

Merging #1553 into cgroups will increase coverage by 0.04%.
The diff coverage is 76.81%.

@@             Coverage Diff             @@
##           cgroups    #1553      +/-   ##
===========================================
+ Coverage    63.18%   63.22%   +0.04%     
===========================================
  Files           78       78              
  Lines        10989    11029      +40     
  Branches      1543     1550       +7     
===========================================
+ Hits          6943     6973      +30     
- Misses        3710     3718       +8     
- Partials       336      338       +2

Impacted Files	Coverage Δ
azurelinuxagent/common/osutil/default.py	55.55% <0%> (-0.07%)	⬇️
azurelinuxagent/common/event.py	82.69% <100%> (ø)	⬆️
azurelinuxagent/common/exception.py	91.35% <100%> (-0.21%)	⬇️
azurelinuxagent/common/logger.py	88.59% <100%> (+1.18%)	⬆️
azurelinuxagent/common/cgroup.py	69.64% <55%> (-1.79%)	⬇️
azurelinuxagent/common/cgroupstelemetry.py	93.7% <76.92%> (-3.5%)	⬇️

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[pgombar]

Will be LGTM after refactoring the periodic_* functions and adding more info to log messages, as Norberto commented.

[pgombar]

LGTM

[narrieta]

thanks