Getting "WARNING: Unknown parameter(s) found for class type 'com.cloudbees.jenkins.plugins.awscredentials.AmazonWebServicesCredentialsBinding': keyIdVariable,secretVariable" from my pipeline

The only relevant line I see is this
```
environment {
AN_ACCESS_KEY = credentials("${params.ENVIRONMENT}")
}
```
Where `${params.ENVIRONMENT}` referes to AWS credentials. The credentials work as expected with build succeeding, it's just a warning that is bothersome

I see the variables reported by the warning are set here -> https://github.com/jenkinsci/aws-credentials-plugin/blob/4f6e283034587c9481e4f50577723f3c111917bb/src/main/java/com/cloudbees/jenkins/plugins/awscredentials/AWSDeclarativeCredentialsHandler.java#L60

Start with src/main/java/com/cloudbees/jenkins/plugins/awscredentials/AWSDeclarativeCredentialsHandler.java around line 60, where keyIdVariable and secretVariable are set. Reproduce the pipeline warning using the credentials expression shown in the issue and trace why those parameters are reported as unknown. Done means the credentials still work and the warning is no longer emitted.

Written by the indexing model from the issue text.