ref(scheduler): remove TransitionError as it is no longer used

Author: helgi

rootfs/scheduler/states.py

@@ -1,15 +1,6 @@
 import enum
 
 
-class TransitionError(Exception):
-    """Raised when a transition from one state to another is illegal"""
-
-    def __init__(self, prev, next, msg):
-        self.prev = prev
-        self.next = next
-        self.msg = msg
-
-
 class JobState(enum.Enum):
     initialized = 1
     created = 2