{Core} refine local context message

[arrownj]

Description
This PR is to fix #14015 .

PM want to refine some of local context message.

Testing Guide

az local-context on

Command group 'local-context' is experimental and not covered by customer support. Please use with discretion.
Local context is turned off, you can run az local-context on to turn it on.

az group create -g xxj -l westus2

Local context is turned on. Its information is saved in working directory D:\code\cli\azure-cli. You can run az local-context off to turn it off.
Your preference of: --name: xxj, --location: westus2 are now saved to local context. To learn more, type in az local-context --help

History Notes

[Component Name 1] BREAKING CHANGE: az command a: Make some customer-facing breaking change.
[Component Name 2] az command b: Add some customer-facing feature.

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[jiasli]

The colon seems weird to me. How about

Suggested change

	logger.warning('Your preference of: %s now saved to local context. To learn more, type in az '
	'local-context --help', ', '.join(args_str) + ' is' if len(args_str) == 1 else ' are')
	logger.warning('Your preference of '%s' are now saved to local context. To learn more, type in `az
	'local-context --help`, ', '.join(args_str) + ' is' if len(args_str) == 1 else ' are')

[jiasli]

We usually use backticks (`) to denote commands. See #13060.

[yonzhan]

Core