Improve documentation for waiters

[aBurmeseDev]

Describe the issue

Current waiter pages could use some examples with more detailed description on the config params. For example: maxWaitTime is a required field for waiter config and it's not mentioned anywhere in the docs.

Here's a blog post about waiters with useful references: https://aws.amazon.com/blogs/developer/waiters-in-modular-aws-sdk-for-javascript/

Links

https://docs.aws.amazon.com/AWSJavaScriptSDK/v3/latest/Package/-aws-sdk-client-s3/Variable/waitUntilBucketExists/

[arianvp]

Please also document the kind of exceptions it returns. This is currently undocumented