Add ui.language.click event for language toggle

[shakao]

[sc-10935]

instrumenting both the menu dropdown and the language toggle!

• ui.language.click: with a locale parameter that will be "en" or "es" (whichever locale the user is switching to)

[shortcut-integration[bot]]

This pull request has been linked to Shortcut Story #10935: [Analytics] Add tick event for the language toggle.