ipatests: ipa-healthcheck test fixes running on RHEL
    
    1. Added function in tasks.py to get healthcheck version.
    2. Added if else condition to certain tests to
    check healthcheck version and then assert the expected test output
    
    Signed-off-by: Sudhir Menon <sumenon@redhat.com>
    Reviewed-By: Florence Blanc-Renaud <flo@redhat.com>