Tools: Improve API Ref links in rendered output

[DavidSouther]

https://github.com/awsdocs/aws-doc-sdk-examples/blob/3ab773803fc78d0957517b5a4e2cc3c084aedfdd/.doc_gen/templates/zonbook/example_language_template.xml#L76

For Rust, this links to https://docs.rs/releases/search?query=aws-sdk for all examples. Kotlin has been observed with similar behavior. We should also check other languages.

https://docs.aws.amazon.com/sdk-for-rust/latest/dg/rust_api-gateway_code_examples.html should link to https://docs.rs/aws-sdk-apigateway/latest/aws_sdk_apigateway/client/struct.Client.html#method.get_rest_apis