chore(ec2): explicit feature flags to produce a consistent template d…

…uring tests (aws#16008)

In v1, the default value of the `@aws-cdk/core:newStyleStackSynthesis` flag is `false`. As a consequence, `Template.fromStack()` generates, by default, a template without the rule and parameter related to bootstrap versions. In v2,  the default value of this flag is `true`. So this test fails in the v2 branch. By explicitly setting the flag to `false`, we ensure that the tests passes on both v1 and v2, regardless of the default values.

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packages/@aws-cdk/aws-ec2/test/client-vpn-authorization-rule.test.ts

@@ -1,11 +1,16 @@
 import '@aws-cdk/assert-internal/jest';
-import { Stack } from '@aws-cdk/core';
+import { App, Stack } from '@aws-cdk/core';
 import { Connections, IClientVpnEndpoint } from '../lib';
 import { ClientVpnAuthorizationRule } from '../lib/client-vpn-authorization-rule';
 
 let stack: Stack;
 beforeEach(() => {
-  stack = new Stack();
+  const app = new App({
+    context: {
+      '@aws-cdk/core:newStyleStackSynthesis': false,
+    },
+  });
+  stack = new Stack(app);
 });
 
 describe('ClientVpnAuthorizationRule constructor', () => {

packages/@aws-cdk/aws-ec2/test/client-vpn-route.test.ts

@@ -1,6 +1,6 @@
 import '@aws-cdk/assert-internal/jest';
 import { SamlMetadataDocument, SamlProvider } from '@aws-cdk/aws-iam';
-import { Stack } from '@aws-cdk/core';
+import { App, Stack } from '@aws-cdk/core';
 import * as ec2 from '../lib';
 import {
   ClientVpnRoute,
@@ -11,7 +11,12 @@ import {
 let stack: Stack;
 let vpc: ec2.IVpc;
 beforeEach(() => {
-  stack = new Stack();
+  const app = new App({
+    context: {
+      '@aws-cdk/core:newStyleStackSynthesis': false,
+    },
+  });
+  stack = new Stack(app);
   vpc = new ec2.Vpc(stack, 'Vpc');
 });