Fix Vector* mixin's docstring (#404)

* Fix VectorNumpy's docstring

* Update object.py

* Update object.py

* Update awkward.py

src/vector/backends/awkward.py

@@ -615,7 +615,7 @@ def __getitem__(self, where: typing.Any) -> float | ak.Array | ak.Record | None:
 
 
 class VectorAwkward:
-    """One dimensional vector class for the Awkward backend."""
+    """Mixin class for Awkward vectors."""
 
     lib: types.ModuleType = numpy
 

src/vector/backends/numpy.py

@@ -733,7 +733,7 @@ def tau(self) -> FloatArray:
 
 
 class VectorNumpy(Vector, GetItem):
-    """One dimensional vector class for the NumPy backend."""
+    """Mixin class for NumPy vectors."""
 
     lib = numpy
     dtype: numpy.dtype[typing.Any]

src/vector/backends/object.py

@@ -330,7 +330,7 @@ def _replace_data(obj: typing.Any, result: typing.Any) -> typing.Any:
 
 
 class VectorObject(Vector):
-    """One dimensional vector class for the object backend."""
+    """Mixin class for Object vectors."""
 
     lib = numpy