[azure] message is unclear when missing clientCertificatePassword in osServicePrincipal.json

Configure certificate for installer Service Principal with passphrase, when only adding clientCertificate into osServicePrincipal.json, installer give the message which is unclear that what's missing and redirect to ask subscription id.

$ ./openshift-install create install-config --dir ipi-test
INFO Could not get an azure authorizer from file: auth file missing client and certificate credentials 
INFO Asking user to provide authentication info   
? azure subscription id [? for help] 

4.13.0-0.nightly-2023-02-17-090603

Always

1. generate certs with passphrase and configure it in SP
2. update osServicePrincipal.json without adding clientCertificatePassword, since this parameter is optional.(Actually, if certs with passphrase, it is required.)
3. create install-config file

The message is unclear what's missing when getting an auth.

The message should give more details that client certificate is found, but failed to auth, make sure that path is correct or clientCertificatePassword is required if certs with passphrase, something like that, so that user know how to correct the file.