docs(cloudwatch): description for cloudwatch alarm actions (#25853)

As mentioned in [the issue](#22801), some of the details of the argument types for the CloudWatch Alarm and CompositeAlarm methods are wrong.

Closes #22801

----

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

packages/aws-cdk-lib/aws-cloudwatch/lib/alarm-base.ts

@@ -57,7 +57,7 @@ export abstract class AlarmBase extends Resource implements IAlarm {
   /**
    * Trigger this action if the alarm fires
    *
-   * Typically the ARN of an SNS topic or ARN of an AutoScaling policy.
+   * Typically SnsAcion or AutoScalingAction.
    */
   public addAlarmAction(...actions: IAlarmAction[]) {
     if (this.alarmActionArns === undefined) {
@@ -70,7 +70,7 @@ export abstract class AlarmBase extends Resource implements IAlarm {
   /**
    * Trigger this action if there is insufficient data to evaluate the alarm
    *
-   * Typically the ARN of an SNS topic or ARN of an AutoScaling policy.
+   * Typically SnsAcion or AutoScalingAction.
    */
   public addInsufficientDataAction(...actions: IAlarmAction[]) {
     if (this.insufficientDataActionArns === undefined) {
@@ -83,7 +83,7 @@ export abstract class AlarmBase extends Resource implements IAlarm {
   /**
    * Trigger this action if the alarm returns from breaching state into ok state
    *
-   * Typically the ARN of an SNS topic or ARN of an AutoScaling policy.
+   * Typically SnsAcion or AutoScalingAction.
    */
   public addOkAction(...actions: IAlarmAction[]) {
     if (this.okActionArns === undefined) {

packages/aws-cdk-lib/aws-cloudwatch/lib/alarm.ts

@@ -250,7 +250,7 @@ export class Alarm extends AlarmBase {
   /**
    * Trigger this action if the alarm fires
    *
-   * Typically the ARN of an SNS topic or ARN of an AutoScaling policy.
+   * Typically SnsAcion or AutoScalingAction.
    */
   public addAlarmAction(...actions: IAlarmAction[]) {
     if (this.alarmActionArns === undefined) {