Remove Event.wrapper for home screen related telemetry

[mcarare]

Breakout from #21292.

┆Issue is synchronized with this Jira Task

[LaurentiuApahideanSV]

I tested the issue on Firefox Nightly 2022-04-19 by interacting with the home screen and observing the results.
Tapping the Settings button from the 3 dot menu
{
"timestamp": 4936,
"category": "home_menu",
"name": "settings_item_clicked"
}

When the home screen is displayed
{
"timestamp": 0,
"category": "home_screen",
"name": "home_screen_displayed"
},

Tapping the Customize button from the 3 dot menu
{
"timestamp": 14677,
"category": "home_screen",
"name": "customize_home_clicked"
},

When the home screen is accessed
{
"timestamp": 0,
"category": "start_on_home",
"name": "enter_home_screen"
},

When opening the tabs tray
{
"timestamp": 10064,
"category": "start_on_home",
"name": "open_tabs_tray"
},
Glean Dashboard

Device used:

• OnePlus 6T (Android 9)