[MA-12]: Add label to form field in channel header

[SaurabhSharma-884]

Summary

Associate visual label with form field in form - Edit the text appearing next to the channel name in the header.

Ticket Link

https://mattermost.atlassian.net/browse/MM-61571

Screenshots

Release Note

NONE

[github-actions]

⚠️ One or more flaky tests detected ⚠️

• Failing job: github.com/mattermost/mattermost:Postgres
• Double check your code to ensure you haven't introduced a flaky test.
• If this seems to be unrelated to your changes, submit a separate pull request to skip the flaky tests (e.g. 23360) and file JIRA ticket (e.g. MM-52743) for later investigation.

Test	Retries
Postgres (Results)
com/mattermost/mattermost/server/v8/channels/api4.TestClientListOutgoingOAuthConnection/filter_by_audience	1
com/mattermost/mattermost/server/v8/channels/api4.TestClientListOutgoingOAuthConnection/return_result	1
com/mattermost/mattermost/server/v8/channels/api4.TestClientListOutgoingOAuthConnection	1

[github-actions]

⚠️ One or more flaky tests detected ⚠️

• Failing job: github.com/mattermost/mattermost:MySQL
• Double check your code to ensure you haven't introduced a flaky test.
• If this seems to be unrelated to your changes, submit a separate pull request to skip the flaky tests (e.g. 23360) and file JIRA ticket (e.g. MM-52743) for later investigation.

Test	Retries
MySQL (Results)
com/mattermost/mattermost/server/v8/channels/api4.TestPublishUserTyping/should_send_typing_event_via_websocket_when_triggering_a_typing_event_for_a_user_with_a_common_channel	1
com/mattermost/mattermost/server/v8/channels/api4.TestPublishUserTyping	1

[github-actions]

⚠️ One or more flaky tests detected ⚠️

• Failing job: github.com/mattermost/mattermost:Postgres with binary parameters
• Double check your code to ensure you haven't introduced a flaky test.
• If this seems to be unrelated to your changes, submit a separate pull request to skip the flaky tests (e.g. 23360) and file JIRA ticket (e.g. MM-52743) for later investigation.

Test	Retries
Postgres with binary parameters (Results)
com/mattermost/mattermost/server/v8/channels/api4.TestUpdateOAuthApp	1