[pre-commit.ci] auto fixes from pre-commit.com hooks

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src/tendo/singleton.py

@@ -15,7 +15,6 @@ class SingleInstanceException(BaseException):
 
 
 class SingleInstance:
-
     """Class that can be instantiated only once per machine.
 
     If you want to prevent your script from running in parallel just instantiate SingleInstance() class. If is there another instance already running it will throw a `SingleInstanceException`.