Remove npm audit issues & add Call SID to intial GET

[paulashfield]

• update NPM packages to remove warnings in 'npm audit'
• Audio file download (within Play) amended to match updated package
• pass the call SID on the query string with the initial GET

This last change is required by our twiML back-end which sets up session parameters when the initial request is made and needs the SID to tie subsequent requests together.