getUrlQueryFromCustomSchemeUrl

Return the Url Query of a given a url having a custom scheme (non-standard http/https). Called when handling Urls from a deep link or Qr code code which requires decoding the url and the custom urlScheme, such as openid-credential-offer://, throws an exception by URLDecoder.decode: " java.net.MalformedURLException: unknown protocol: openid-credential-offer"

This function getUrlQueryFromCustomSchemeUrl avoids the exception from being thrown by attempting to convert the provided url String to a URI and return the query property.

If the url does not contain an authority, an Exception will be thrown when trying to convert the Url to a URI, so placeholder authority is provided for the sake of creating a valid Uri and obtaining the query value successfully.