fix: limit query parameter parsing in auth admin api

[sobolk]

Description of changes

This PR fixes an error where limit in Auth Admin API templates would be passed incorrectly to Cognito SDK as string whereas SDK expects number.

I.e. this error:

SerializationException: STRING_VALUE can not be converted to an Integer
    at throwDefaultError (/var/runtime/node_modules/@aws-sdk/smithy-client/dist-cjs/default-error-handler.js:8:22)
    at deserializeAws_json1_1ListUsersInGroupCommandError (/var/runtime/node_modules/@aws-sdk/client-cognito-identity-provider/dist-cjs/protocols/Aws_json1_1.js:5121:51)
    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
    at async /var/runtime/node_modules/@aws-sdk/middleware-serde/dist-cjs/deserializerMiddleware.js:7:24
    at async /var/runtime/node_modules/@aws-sdk/middleware-signing/dist-cjs/middleware.js:13:20
    at async StandardRetryStrategy.retry (/var/runtime/node_modules/@aws-sdk/middleware-retry/dist-cjs/StandardRetryStrategy.js:51:46)
    at async /var/runtime/node_modules/@aws-sdk/middleware-logger/dist-cjs/loggerMiddleware.js:6:22
    at async listUsersInGroup (/var/task/cognitoActions.js:231:20)
    at async /var/task/app.js:229:18 {

Issue #, if available

Description of how you validated changes

Added e2e tests that are calling Auth Admin API

Checklist

• PR description included
• yarn test passes
• Tests are changed or added
• Relevant documentation is changed or added (and PR referenced)
• New AWS SDK calls or CloudFormation actions have been added to relevant test and service IAM policies
• Pull request labels are added

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

[0618]

LGTM. Thanks for adding the test.

Just left some non-blocking nits and questions.