Report and cleanup handlers only if GS supported

[larohra]

Description

Report and cleanup extension handlers only if last GoalState was supported.
Incase it was unsupported, we should report the state of the extensions in the VM over what the new GS was asking us for and skip cleanup too.

Issue #

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PR information

• The title of the PR is clear and informative.
• 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.
• If applicable, the PR references the bug/issue that it fixes in the description.
• New Unit tests were added for the changes made

Quality of Code and Contribution Guidelines

• I have read the contribution guidelines.

[codecov]

Codecov Report

Merging #2206 (14f2ed2) into develop (cc6ee4e) will increase coverage by 0.07%.
The diff coverage is 80.76%.

@@             Coverage Diff             @@
##           develop    #2206      +/-   ##
===========================================
+ Coverage    70.43%   70.51%   +0.07%     
===========================================
  Files           96       96              
  Lines        13548    13564      +16     
  Branches      1910     1915       +5     
===========================================
+ Hits          9542     9564      +22     
+ Misses        3593     3590       -3     
+ Partials       413      410       -3     

Impacted Files	Coverage Δ
azurelinuxagent/ga/exthandlers.py	86.81% <80.76%> (+0.09%)	⬆️
azurelinuxagent/ga/collect_telemetry_events.py	92.12% <0.00%> (+2.39%)	⬆️

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[narrieta]

LGTM; couple of comments