chore: fix build break caused by exported deprecated functions (#17719)

Functions (not member methods) aren't acknowledged by jsii, so they are not
stripped out of the compiled source, even when deprecated. These two functions
are deprecated and reference deprecated interfaces. When running the init
template tests against JS/TS, the tests fail with:

```
node_modules/aws-cdk-lib/aws-elasticloadbalancingv2/lib/alb/application-listener-rule.d.ts(110,62): error TS2304: Cannot find name 'FixedResponse'.
node_modules/aws-cdk-lib/aws-elasticloadbalancingv2/lib/alb/application-listener-rule.d.ts(116,68): error TS2304: Cannot find name 'RedirectResponse'.
```

By -- on v2 only -- un-exporting the functions and inlining them in their
secondary usages, we can effectively "strip" these functions from the JS/TS.


----

*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-elasticloadbalancingv2/lib/alb/application-listener-rule.ts

@@ -391,7 +391,7 @@ export class ApplicationListenerRule extends Construct {
  * @internal
  * @deprecated
  */
-export function validateFixedResponse(fixedResponse: FixedResponse) {
+function validateFixedResponse(fixedResponse: FixedResponse) {
   if (fixedResponse.statusCode && !/^(2|4|5)\d\d$/.test(fixedResponse.statusCode)) {
     throw new Error('`statusCode` must be 2XX, 4XX or 5XX.');
   }
@@ -406,7 +406,7 @@ export function validateFixedResponse(fixedResponse: FixedResponse) {
  * @internal
  * @deprecated
  */
-export function validateRedirectResponse(redirectResponse: RedirectResponse) {
+function validateRedirectResponse(redirectResponse: RedirectResponse) {
   if (redirectResponse.protocol && !/^(HTTPS?|#\{protocol\})$/i.test(redirectResponse.protocol)) {
     throw new Error('`protocol` must be HTTP, HTTPS, or #{protocol}.');
   }

packages/@aws-cdk/aws-elasticloadbalancingv2/lib/alb/application-listener.ts

@@ -10,7 +10,7 @@ import { IListenerCertificate, ListenerCertificate } from '../shared/listener-ce
 import { determineProtocolAndPort } from '../shared/util';
 import { ListenerAction } from './application-listener-action';
 import { ApplicationListenerCertificate } from './application-listener-certificate';
-import { ApplicationListenerRule, FixedResponse, RedirectResponse, validateFixedResponse, validateRedirectResponse } from './application-listener-rule';
+import { ApplicationListenerRule, FixedResponse, RedirectResponse } from './application-listener-rule';
 import { IApplicationLoadBalancer } from './application-load-balancer';
 import { ApplicationTargetGroup, IApplicationLoadBalancerTarget, IApplicationTargetGroup } from './application-target-group';
 import { ListenerCondition } from './conditions';
@@ -377,7 +377,18 @@ export class ApplicationListener extends BaseListener implements IApplicationLis
       messageBody: props.messageBody,
     };
 
-    validateFixedResponse(fixedResponse);
+    /**
+     * NOTE - Copy/pasted from `application-listener-rule.ts#validateFixedResponse`.
+     * This was previously a deprecated, exported function, which caused issues with jsii's strip-deprecated functionality.
+     * Inlining the duplication functionality in v2 only (for now).
+     */
+    if (fixedResponse.statusCode && !/^(2|4|5)\d\d$/.test(fixedResponse.statusCode)) {
+      throw new Error('`statusCode` must be 2XX, 4XX or 5XX.');
+    }
+
+    if (fixedResponse.messageBody && fixedResponse.messageBody.length > 1024) {
+      throw new Error('`messageBody` cannot have more than 1024 characters.');
+    }
 
     if (props.priority) {
       new ApplicationListenerRule(this, id + 'Rule', {
@@ -410,7 +421,18 @@ export class ApplicationListener extends BaseListener implements IApplicationLis
       statusCode: props.statusCode,
     };
 
-    validateRedirectResponse(redirectResponse);
+    /**
+     * NOTE - Copy/pasted from `application-listener-rule.ts#validateRedirectResponse`.
+     * This was previously a deprecated, exported function, which caused issues with jsii's strip-deprecated functionality.
+     * Inlining the duplication functionality in v2 only (for now).
+     */
+    if (redirectResponse.protocol && !/^(HTTPS?|#\{protocol\})$/i.test(redirectResponse.protocol)) {
+      throw new Error('`protocol` must be HTTP, HTTPS, or #{protocol}.');
+    }
+
+    if (!redirectResponse.statusCode || !/^HTTP_30[12]$/.test(redirectResponse.statusCode)) {
+      throw new Error('`statusCode` must be HTTP_301 or HTTP_302.');
+    }
 
     if (props.priority) {
       new ApplicationListenerRule(this, id + 'Rule', {