Feature: Add option to install multiple candidates in one go

[yeikel]

• I have read the CONTRIBUTING guidelines
• I've had a conversation on the #cli-development Slack channel about this request.
  • I cannot reach out to that channel in my environment and my only option is to discuss it here

Feature request

I executed the following command

sdk install java 17.0.8-amzn 20.0.2-amzn

And sdkman happily accepted it and only installed 17.0.8-amzn.

I think that sdkman should either fail with an error OR allow this usage. Otherwise, it is confusing to see that it only installs one of them

~ sdk install java 17.0.8-amzn 20.0.2-amzn

Downloading: java 17.0.8-amzn

In progress...

########################################################################################################################## 100.0%

Repackaging Java 17.0.8-amzn...

Done repackaging...
Cleaning up residual files...

Installing: java 17.0.8-amzn
Done installing!

Do you want java 17.0.8-amzn to be set as default? (Y/n): n