feat(kinesisanalytics-flink): add support for Flink 1.18 (#29554)

### Reason for this change

Amazon Kinesis Data Analytics now supports Apache Flink v1.18 ([LINK](https://aws.amazon.com/about-aws/whats-new/2024/03/amazon-managed-service-apache-flink-support-1-18/))

This is also supported in Cloudformation ([LINK](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-kinesisanalyticsv2-application.html#aws-resource-kinesisanalyticsv2-application-properties))

### Description of changes

- Added Flink 1.18 to `Runtime` type
- Updated Readme to reference Flink 1.18

### Checklist
- [x] My code adheres to the [CONTRIBUTING GUIDE](https://github.com/aws/aws-cdk/blob/main/CONTRIBUTING.md) and [DESIGN GUIDELINES](https://github.com/aws/aws-cdk/blob/main/docs/DESIGN_GUIDELINES.md)

----

*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-kinesisanalytics-flink-alpha/README.md

@@ -46,7 +46,7 @@ const flinkApp = new flink.Application(this, 'Application', {
     },
   },
   // ...
-  runtime: flink.Runtime.FLINK_1_15,
+  runtime: flink.Runtime.FLINK_1_18,
   code: flink.ApplicationCode.fromBucket(bucket, 'my-app.jar'),
 });
 ```
@@ -59,7 +59,7 @@ snapshotting, monitoring, and parallelism.
 declare const bucket: s3.Bucket;
 const flinkApp = new flink.Application(this, 'Application', {
   code: flink.ApplicationCode.fromBucket(bucket, 'my-app.jar'),
-  runtime: flink.Runtime.FLINK_1_15,
+  runtime: flink.Runtime.FLINK_1_18,
   checkpointingEnabled: true, // default is true
   checkpointInterval: Duration.seconds(30), // default is 1 minute
   minPauseBetweenCheckpoints: Duration.seconds(10), // default is 5 seconds
@@ -80,7 +80,7 @@ declare const bucket: s3.Bucket;
 declare const vpc: ec2.Vpc;
 const flinkApp = new flink.Application(this, 'Application', {
   code: flink.ApplicationCode.fromBucket(bucket, 'my-app.jar'),
-  runtime: flink.Runtime.FLINK_1_15,
+  runtime: flink.Runtime.FLINK_1_18,
   vpc,
 });
 ```

packages/@aws-cdk/aws-kinesisanalytics-flink-alpha/lib/types.ts

@@ -66,6 +66,9 @@ export class Runtime {
   /** Flink Version 1.15 */
   public static readonly FLINK_1_15 = Runtime.of('FLINK-1_15');
 
+  /** Flink Version 1.18 */
+  public static readonly FLINK_1_18 = Runtime.of('FLINK-1_18');
+
   /** Create a new Runtime with with an arbitrary Flink version string */
   public static of(value: string) {
     return new Runtime(value);

packages/@aws-cdk/aws-kinesisanalytics-flink-alpha/test/integ.application-code-from-bucket.lit.js.snapshot/FlinkAppCodeFromBucketTest.template.json

@@ -147,13 +147,6 @@
   "AppF1B96344": {
    "Type": "AWS::KinesisAnalyticsV2::Application",
    "Properties": {
-    "RuntimeEnvironment": "FLINK-1_11",
-    "ServiceExecutionRole": {
-     "Fn::GetAtt": [
-      "AppRole1AF9B530",
-      "Arn"
-     ]
-    },
     "ApplicationConfiguration": {
      "ApplicationCodeConfiguration": {
       "CodeContent": {
@@ -181,6 +174,13 @@
      "ApplicationSnapshotConfiguration": {
       "SnapshotsEnabled": true
      }
+    },
+    "RuntimeEnvironment": "FLINK-1_18",
+    "ServiceExecutionRole": {
+     "Fn::GetAtt": [
+      "AppRole1AF9B530",
+      "Arn"
+     ]
     }
    },
    "DependsOn": [

packages/@aws-cdk/aws-kinesisanalytics-flink-alpha/test/integ.application-code-from-bucket.lit.ts

@@ -15,7 +15,7 @@ const fileKey = asset.s3ObjectKey;
 ///! show
 new flink.Application(stack, 'App', {
   code: flink.ApplicationCode.fromBucket(bucket, fileKey),
-  runtime: flink.Runtime.FLINK_1_11,
+  runtime: flink.Runtime.FLINK_1_18,
 });
 ///! hide