Add telemetry for new tab menu traffic

[carlos-zamora]

Summary of the Pull Request

Adds new telemetry events to track traffic through the new tab menu. Specifically, the following events are added:

• NewTabMenuDefaultButtonClicked: Event emitted when the default button from the new tab split button is invoked
• NewTabMenuOpened: Event emitted when the new tab menu is opened
• NewTabMenuClosed: Event emitted when the new tab menu is closed
• NewTabMenuItemClicked: Event emitted when an item from the new tab menu is invoked
  • Has an ItemType parameter that can be set to Settings, CommandPalette, About, Profile, Action`
  • Has a TabCount parameter that keeps tracked of the number of tabs in the window before changing the state
• NewTabMenuCreatedNewTerminalSession: Event emitted when a new terminal was created via the new tab menu
  • Has a SessionType parameter that can be set to ElevatedWindow, Window, Pane, Tab
  • Instead of TabCount, has a NewTabCount that keeps track of the new number of tabs after the session has been created
• NewTabMenuItemElevateSubmenuItemClicked: Event emitted when the elevate submenu item from the new tab menu is invoked

Validation Steps Performed

Used TVPP to see events generated from interacting with the new tab menu.