Description of problem:
incorrect option base64 -D when generating the command to import a cluster
the correct option is -d ; this could throw errors.

Version-Release number of selected component (if applicable):
2.2.1

How reproducible:
customer environment

Steps to Reproduce:
1. Login in the the RAHCM Console
2. Menu > Automate Infrastructure > Clusters
3. Add a cluster > Import an existing cluster
4. Fill any value for the cluster name
5. Click on "Save import and generate code"
6. Click on "Copy command"
7. Paste the command 

Actual results:
the command ends with "| base64 -D" which can raise an error.

Expected results:
the command ends with "| base64 -d" 

Additional info:
openshift 4.6.22 was used on the customer environment.