ulab: docs: Fix markup error

Author: jepler

shared-bindings/ulab/vector/__init__.pyi

@@ -112,7 +112,7 @@ def vectorize(f, *, otypes=None):
     :param callable f: The function to wrap
     :param otypes: List of array types that may be returned by the function.  None is intepreted to mean the return value is float.
 
-    Wrap a Python function `f` so that it can be applied to arrays.
+    Wrap a Python function ``f`` so that it can be applied to arrays.
 
     The callable must return only values of the types specified by otypes, or the result is undefined."""
     ...