Add log grouping to AzureCLIv2

[MariusStorhaug]

Task name:
AzureCLIv2

Description:
Added Log grouping around the login commands, so that when the context of an account has multiple subscriptions has access to, that will be shown optionally (by extending the log group). Instead of having the long list of contexts, I added a command to show current context if it is selected.

The current implementation here uses console.log('##[group]Name'); and console.log('##[endgroup]');, but I have a PR (microsoft/azure-pipelines-task-lib#994) I am working on to get the functionality into the library (azure-pipelines-task-lib/task). After this is done, the lines would instead say tl.group('Name'); and tl.endgroup();. If you agree to adding the functionality, we should add this as a initial go at it, and then refactor it to use the new functions available in the lib later on.

I also have some auto formatting, cleaning code a bit and fixing alignments.

Documentation changes required:
Not needed

Added unit tests:
N/A

Attached related issue:

• Fixes: [enhancement]: AzureCLI - Group verbose output #19246

Checklist:

• Task version was bumped - please check instruction how to do it
• Checked that applied changes work as expected