Field mapping UI component: Toggle button with medium and small size prop values

Purpose: To create a new UI component: Toggle button with medium and small size prop values. This new component is needed for the Data Import Field Mapping details UI.

Key links:

• Prototype of item record field mapping details: https://ux.folio.org/testing/data-import/1004/
• Intro meeting recording: 20200108 Field Mapping Details Intro Mtg
  https://ebscomeetings.webex.com/recordingservice/sites/ebscomeetings/recording/playback/82e2b90f72124c6b88734217c49a5537
• Intro meeting notes: https://docs.google.com/document/d/1HY4SGhqbTi8pZlsyRGfUn-62NmMVzb7ObLFUVtskK44/edit#

Requirements

• When toggled "off", it is grey and the button is on the left
• When toggled "on", it is blue and the button is on the right
• Can be toggled manually by the user or automatically by the system

See attached images