fix(eks): integ tests errors (#24276)

This PR fixes the integ tests errors in aws-eks and addresses the following issues:

`integ.alb-controller.ts` has `runAsNonRoot` error and should define a non-root user in securityContext of the pod definition to ensure successful k8s deployment.

`integ.eks-service-account-sdk-call.ts` should define a non-root user as well and increase the timeout of `BucketPinger` from the default 1 min to 3 min as the deployment could take up to 2 minutes or more. The base docker image from docker hub for this test has been replaced with the same image in ECR public to avoid potential throttling.

I have manually run the two integ tests in my account and both successfully deploy with no error now.

Closes #24266

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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*

Author: pahud

Diff for: packages/@aws-cdk/aws-eks/test/bucket-pinger/bucket-pinger.ts

@@ -6,6 +6,7 @@ import { Construct } from 'constructs';
 
 export interface BucketPingerProps {
   readonly bucketName: string;
+  readonly timeout?: Duration;
 }
 export class BucketPinger extends Construct {
 
@@ -18,7 +19,7 @@ export class BucketPinger extends Construct {
       code: lambda.Code.fromAsset(`${__dirname}/function`),
       handler: 'index.handler',
       runtime: lambda.Runtime.PYTHON_3_9,
-      timeout: Duration.minutes(1),
+      timeout: props.timeout ?? Duration.minutes(1),
       environment: {
         BUCKET_NAME: props.bucketName,
       },