Fix Wowza test when Wowza is not installed

tests/scripts/test_wowza.py

@@ -81,7 +81,7 @@ def check_installed_and_enabled() -> bool:
 
     cmd = 'dpkg --get-selections "wowza*"'
     out = subprocess.getoutput(cmd).strip()
-    state = out.split()[-1]
+    state = out.split('\t')[-1]
     if state != 'install':
         lg.info('not installed, skip test')
         return False