[AWS]Installer should have pre-check for user tags

    4.18

    always

Setting user tags as below in install-config: 

    userTags:
      usage-user: cloud-team-rebase-bot[bot]

The user tags will be applied to many resources, including roles, but [] does not allowed to tag to roles

https://drive.google.com/file/d/148y-cYrfzNQzDwWlUrgMYAGsZAY6gbW4/view?usp=sharing

    

Installation failed as failed to create IAM roles, ref job: https://prow.ci.openshift.org/view/gs/test-platform-results/pr-logs/pull/openshift_cluster-api-provider-aws/529/pull-ci-openshift-cluster-api-provider-aws-master-regression-clusterinfra-aws-ipi-proxy-techpreview/1852197133122277376

Installer should have pre-check for this scenario and exit with error message if user tags contain unsupported chars  

    discussion on slack: https://redhat-internal.slack.com/archives/CF8SMALS1/p1730443557188649