feat(cloudfront): add amplify managed cache policy (#16880)

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*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

packages/@aws-cdk/aws-cloudfront/lib/cache-policy.ts

@@ -85,9 +85,13 @@ export interface CachePolicyProps {
  * A Cache Policy configuration.
  *
  * @resource AWS::CloudFront::CachePolicy
+ * @link https://docs.aws.amazon.com/AmazonCloudFront/latest/DeveloperGuide/using-managed-cache-policies.html
  */
 export class CachePolicy extends Resource implements ICachePolicy {
-
+  /**
+   * This policy is designed for use with an origin that is an AWS Amplify web app.
+   */
+  public static readonly AMPLIFY = CachePolicy.fromManagedCachePolicy('2e54312d-136d-493c-8eb9-b001f22f67d2');
   /**
    * Optimize cache efficiency by minimizing the values that CloudFront includes in the cache key.
    * Query strings and cookies are not included in the cache key, and only the normalized 'Accept-Encoding' header is included.