Update fgpyo/util/metric.py

typo

Co-authored-by: Clint Valentine <[email protected]>

Author: TedBrookings

fgpyo/util/metric.py

@@ -10,7 +10,7 @@
 
 The :class:`~fgpyo.util.metric.Metric` class makes it easy to read, write, and store one or metrics
 of the same type, all the while preserving types for each value in a metric.  It is an abstract
-base class decorated by `dataclassees <https://docs.python.org/3/library/dataclasses.html>`_, or
+base class decorated by `@dataclass <https://docs.python.org/3/library/dataclasses.html>`_, or
 `attr <https://www.attrs.org/en/stable/examples.html>`_, with attributes storing one or more typed
 values.