[Feature]: Build an example of a language dropdown for shiny.i18n

[can-taslicukur]

Guidelines

• I agree to follow this project's Contributing Guidelines.

Description

Add an example shiny.i18n application that includes a dropdown similar to the gif in README

Problem

There is no shiny app example for the dropdown gif in README

Proposed Solution

An example shiny app will be added to the examples folder
Example shiny app will look the same as the gif in README

Alternatives Considered

A function for running the example app could also be added to the package