upgrade cspell and fix spelling issues

backend/src/Model/sparkplugb.ts

@@ -1,9 +1,11 @@
+// cSpell:words protobuf
 import * as protobuf from 'protobufjs'
 import protocol from './sparkplugb.proto'
 import { Base64Message } from './Base64Message'
 import { Decoder } from './Decoder'
 
 const root = protobuf.parse(protocol).root
+/* cspell:disable-next-line */
 export let SparkplugPayload = root.lookupType('com.cirruslink.sparkplug.protobuf.Payload')
 
 export const SparkplugDecoder = {