Fix typeDefs

server/src/resolvers/Log.js

@@ -1,5 +1,4 @@
 const Log = {
-  tags: _ => `[${_.tags.join(', ')}]`,
   data: _ => JSON.stringify(_.data),
   timestamp: _ => _.timestamp?.toISOString()
 }

server/src/typeDefs.js

@@ -190,7 +190,7 @@ const typeDefs = gql`
     id: ID!
     timestamp: String!
     level: LogLevel!
-    tags: String
+    tags: [String]!
     message: String
     data: String
   }