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

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src/pyhf/events.py

@@ -73,7 +73,7 @@ def __call__(self, *args, **kwargs):
             else:
                 func()(*args, **kwargs)
         # We have to flush after calling all the callbacks, not before. That's
-        # beacause, earlier callbacks might cause new dead arg weakrefs in
+        # because, earlier callbacks might cause new dead arg weakrefs in
         # later callbacks. So we check for dead weakrefs in each iteration
         # and then we flush at the end.
         self._flush()