Adding label for PR smoke tests

[prapti]

Adding @smoke tags to 7 pre-existing E2E tests for PR smoke test, which takes roughly 5 minutes to run.
This PR covers smoke tests in the following E2E test files and were selected based on preliminary review of the Smoke Tests doc.

• User can create a new team -- create_a_team_spec
• User can create a channel -- accessibility_sidebar_spec
• Users can join an existing channel -- add_users_to_channel_spec
• User can post in a channel -- message_spec
• Basic search function -- search_user_post
• System administrator can access system console -- demoted_user_spec (changed this from cluster_spec to add a more consistently passing test)
• User can log out -- tutorial_navigation_and_links_spec

To run the tests, please run the following:
node run_tests.js --group='@smoke'

[saturninoabril]

@prapti Looks good to me. Just few requests:

• add more details in the description like how many test cases were initially selected and the duration it takes to run the test
• can't see the "Smoke Tests" doc mentioned in the description. Can you link it here for reference? The only reference I have is the one you posted in our GM
• please add follow up documentation to https://developers.mattermost.com/contribute/webapp/end-to-end-tests/ on how it's selected, what are the criteria and how to run like should it be with args --group="@smoke" only or in combination with prod --stage="@prod" --group="@smoke"
• can you confirm that all are consistently passing? The last time I checked was marketplace_spec still have failing tests that need to attend to.

[prapti]

Thanks for a quick check @saturninoabril! I'll add make those changes and update the PR description. Meanwhile, I've changed it to a WIP PR for now as I'm running some tests from the smoke group to gather some data upfront. I'll update the PR soon. And thanks for reminding that the marketplace tests aren't 100%. Will need to remove them now until fixed.

[saturninoabril]

I'm confused how do you plan to run this.
If @smoke will be on "Group" metadata which I think makes sense, then the @smoke tags on "Stage" can be removed. With that, it could run as node run_tests.js --stage='@prod' --group'@smoke'

Suggested change

	// Stage: @prod @smoke
	// Group: @accessibility
	// Group: @accessibility @smoke
	// Stage: @prod
	// Group: @accessibility @smoke

[saturninoabril]

Oh, I just read your updated description with node run_tests.js --stage='@smoke' --group='@smoke'. However, passing @smoke on both args feels redundant to me.

[prapti]

Removed '@smoke' tag from all other specs not intended for smoke tests. Now that the tag has been added as "Group", the tests can be run simply with --group='@smoke' flag for running the smoke tests, or with --stage='@prod' --group='@smoke' to run it within the production tests.

[saturninoabril]

Awesome, thanks @prapti!

[srkgupta]

LGTM. Approving the PR. Thanks.

[josephbaylon]

LGTM