{Telemetry|Feedback} add installer data

[fengzhou-msft]

Resolve #9013

History Notes:
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[Component Name 1] (BREAKING CHANGE:) (az command:) make some customer-facing change.
[Component Name 2] (BREAKING CHANGE:) (az command:) make some customer-facing change.

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[yonzhan]

Telemetry

[haroldrandom]

Why added AZ_INSTALLER? Fix something?

[jiasli]

The current UA is like

'User-Agent': 'python/3.8.2 (Windows-10-10.0.18362-SP0) msrest/0.6.11 msrest_azure/0.6.2 azure-mgmt-resource/8.0.1 Azure-SDK-For-Python AZURECLI/2.2.0'

Maybe we can append the content of ENV_AZ_INSTALLER to UA_AGENT and make it like AZURECLI/2.2.0 (PIP)?

azure-cli/src/azure-cli-core/azure/cli/core/commands/client_factory.py

Line 18 in 31a9724

UA_AGENT = "AZURECLI/{}".format(core_version)

This is like what Chrome does:

Mozilla/5.0 (Linux; Android 6.0; Nexus 5 Build/MRA58N) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.149 Mobile Safari/537.36

My two cents.

[jiasli]

The same logic is also needed by az rest:

azure-cli/src/azure-cli-core/azure/cli/core/util.py

Lines 556 to 558 in 31a9724

	headers.update({
	'User-Agent': UA_AGENT,
	})

Maybe we can extract the header handling logic to src/azure-cli-core/azure/cli/core/util.py?

[jiasli]

#12734 is merged. We can merge from dev and put the logic in get_az_user_agent.