Implementation for get_all_updates

[SathishMSFT]

What is in this PR:
[X] Minimum pro client version
[X] Skeleton get_all_updates
[X] Implement get_all_updates
[X] Implement get_security_updates
[X] Implement get_security_esm_updates
[X] Implement is_pro_client_attached method and add it to error object
[X] Common code changes( e.g.. status update to reflect esm packages ...)
[X] Testing patching and assessment operation.
[X] Mark Patching operation failed when there are esm packages to updates and VM not attached.
[X] Add error details for assessment where VM is un-attached and has esm packages.
[X] Implement changes to skip and fail esm packages on a un-attached VM. Mark the overall status as "Warning" in this scenario.
[X] Additional error condition checks
[X] Testing on supported versions (18.04), and unsupported versions (20.04).
[X] Unit test coverage..
[X] Add error detail of reboot status when we set status as warning.
[] Adding Telemetry data points for both reboot status and updates.

• Reboot status using pro and mismatch count.
• esm package count. if possible
• updates mismatch count.

What will not be in this PR:

• ESM changes for base apt
• pro api changes to get updates (This will depend on when canonical fixes it)

[rane-rajasi]

@SathishMSFT, code coverage failed for python 3 and hence did not run for python 2. Please check and ensure both of these succeed.

[SathishMSFT]

@SathishMSFT, code coverage failed for python 3 and hence did not run for python 2. Please check and ensure both of these succeed.

Failed intermittently. Re-ran passed.

[kjohn-msft]

@rane-rajasi please review for final pass.

[rane-rajasi]

@SathishMSFT 3 minor comments active from me. 2 are from last review, and 1 is a todo after PR merge, please look into it. Outside of it everything looks good.

[SathishMSFT]

@SathishMSFT 3 minor comments active from me. 2 are from last review, and 1 is a todo after PR merge, please look into it. Outside of it everything looks good.

I have addressed the unittest. Will skip the method name change as there is already property by same name. Will work with John to get the document updated once checked in.