Very tiny typo fix (dotnet#5186)

This is a tiny typo fix, but it is a legitimate typo. My apologies if the ROI of this PR aren't very great.

Author: BrianMcBrayer

xml/System.Threading.Tasks/Task.xml

@@ -722,7 +722,7 @@
           <format type="text/markdown"><![CDATA[  
   
 ## Remarks  
- This property returns a task whose <xref:System.Threading.Tasks.Task.Status%2A> property is set to <xref:System.Threading.Tasks.TaskStatus.RanToCompletion>. To create task that returns a value and runs to completion, call the <xref:System.Threading.Tasks.Task.FromResult%2A> method.  
+ This property returns a task whose <xref:System.Threading.Tasks.Task.Status%2A> property is set to <xref:System.Threading.Tasks.TaskStatus.RanToCompletion>. To create a task that returns a value and runs to completion, call the <xref:System.Threading.Tasks.Task.FromResult%2A> method.  
   
  Repeated attempts to retrieve this property value may not always return the same instance.