When there is an apostrophe in the body the validation of the webhook fails

Issue Summary

An apostrophe in the body of a text message causes validation of Twilio webhook to fail

Steps to Reproduce

1. Send a text message with an apostrophe in it
2. try to validate the incoming webhook

Code Snippet

    twilio_signature = env["HTTP_X_TWILIO_SIGNATURE"]
        url = "#{rack_request.scheme}://" + env["HTTP_HOST"] + env["REQUEST_URI"]
        unless validator.validate(url, {}, twilio_signature)
          raise "Twilio request validation failed."
        end

Technical details:

• twilio-ruby version: 5.40.0 (also fails with 5.37.0)
• ruby version: 2.7.1

Start at the validator.validate call shown in the issue and reproduce webhook validation with a message containing an apostrophe. Trace the signature-validation path and verify that the same request validates successfully once the bug is addressed.