Add Snowplow tracking attributes to the User Menu

What does this MR do and why?

Adds Snowplow tracking to the User Menu items in the new navigation sidebar

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➕ - new tracking event (was not tracked in the old user menu)

⚠ - changed some value in the new tracking event

Tracking events

User menu item	Action	Label	Property
User name (profile link)	click_link	user_profile	nav_user_menu
Set/Edit status	click_button	user_edit_status	nav_user_menu ⚠ previous was undefined
Start an Ultimate trial ➕	click_link	start_trial	nav_user_menu
Edit profile	click_link	user_edit_profile	nav_user_menu
Preferences	click_link	user_preferences	nav_user_menu
Buy Pipeline minutes ➕	click_link	buy_pipeline_minutes	nav_user_menu
Switch to GitLab Next	click_link	switch_to_canary	nav_user_menu
New navigation toggle	click_toggle	disable_new_nav_beta	⚠ nav_user_menu previous was navigation
Feedback Item ➕	click_link	provide_nav_beta_feedback	nav_user_menu
Sign Out	click_link	user_sign_out	nav_user_menu

Screenshots or screen recordings

How to set up and validate locally

1. Enable the super_sidebar_nav feature flag.
2. Log into the GDK and enable the New Navigation for the current user via the User Menu
3. Enable snowplow-micro in your local GDK
4. Install the Snowplow extenion in Google Chrome (optional)
5. Click on any item in the user menu and make sure that the event is tracked (either check that request to tp2 endpoint is sent or it is slightly more obvious with Snowplow Chrome Extension)

Related to #402713 (closed)