Simplify error message formatting in path parameter validation.

Author: hckhanh

src/index.ts

@@ -181,8 +181,7 @@ function validatePathParam(params: ParamMap, key: string) {
 
   if (type !== 'boolean' && type !== 'string' && type !== 'number') {
     throw new TypeError(
-      `Path parameter ${key} cannot be of type ${type}. ` +
-        'Allowed types are: boolean, string, number.',
+      `Path parameter ${key} cannot be of type ${type}. Allowed types are: boolean, string, number.`,
     )
   }