Update lib/rules/no-wait-for-snapshot.ts

Co-authored-by: Gonzalo D'Elia <gonzalo.n.delia@gmail.com>

Author: Gpx

lib/rules/no-wait-for-snapshot.ts

@@ -76,8 +76,9 @@ export default ESLintUtils.RuleCreator(getDocsUrl)<Options, MessageIds>({
       },
       'Program:exit'() {
         const testingLibraryUtilUsage = asyncUtilsUsage.filter(usage => {
-          if (usage.node.type === 'MemberExpression') {
-            const object = usage.node.object as TSESTree.Identifier;
+          if (isMemberExpression(usage.node)) {
+           // object is automatically a TSESTree.Identifier
+            const object = usage.node.object;
 
             return importedAsyncUtils.includes(object.name);
           }