fix: Handle application errors in Sentry (#1982)

- Handle notification errors for attachment messages
- Fix empty identifiers being passed
- Fix 404 when invalid source id
- Handle webhook exceptions

lib/exception_list.rb

@@ -1,4 +1,5 @@
 module ExceptionList
   URI_EXCEPTIONS = [Errno::ETIMEDOUT, Errno::ECONNREFUSED, URI::InvalidURIError, Net::OpenTimeout, SocketError].freeze
-  REST_CLIENT_EXCEPTIONS = [RestClient::NotFound, RestClient::GatewayTimeout, RestClient::BadRequest, RestClient::MethodNotAllowed].freeze
+  REST_CLIENT_EXCEPTIONS = [RestClient::NotFound, RestClient::GatewayTimeout, RestClient::BadRequest,
+                            RestClient::MethodNotAllowed, RestClient::Forbidden].freeze
 end