fix(test): remove wrong error throw

Author: michaelwittwer

src/dynamo/expression/param-util.ts

@@ -68,7 +68,7 @@ type UpdateExpressionsByKeyword = Record<UpdateActionKeyword, string>
 export function mergeUpdateExpressions(expression1: string, expression2: string): string {
   const a = splitUpdateExpressionToActionKeyword(expression1)
   const b = splitUpdateExpressionToActionKeyword(expression2)
-  return Array.from(new Set(<UpdateActionKeyword[]>[...Object.keys(a), ... Object.keys(b)]))
+  return Array.from(new Set(<UpdateActionKeyword[]>[...Object.keys(a), ...Object.keys(b)]))
     .map(clause => `${clause} ` + (!a[clause] ? b[clause] : !b[clause] ? a[clause] : `${a[clause]}, ${b[clause]}`))
     .join(' ')
 }
@@ -85,8 +85,6 @@ function splitUpdateExpressionToActionKeyword(updateExpression: string): UpdateE
     .reduce((u, e, i, arr) => {
       if (isUpdateActionKeyword(e)) {
         u[e] = arr[i + 1]
-      } else {
-        throw new Error(`unknown action keyword ${e}`)
       }
 
       return u