Fix: DNF have less parameters than yum

Author: naparuba

opsbro/system_backends/system_backend_yum.py

@@ -51,7 +51,7 @@ def _try_detect_dnf(self):
             return
         try:
             p = subprocess.Popen(['dnf5', '--version'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
-        except subprocess.SubprocessError:
+        except (subprocess.SubprocessError, FileNotFoundError):
             self._is_dnf = False
             self._is_dnf_detected = True
             return