DOCSP-36080: Add DateFromString to list of supported LINQ methods (mongodb#363)

(cherry picked from commit 3293b42)

Author: mcmorisi

source/fundamentals/linq.txt

@@ -779,8 +779,7 @@ the :ref:`<csharp-builders-out>` section.
 Supported Methods
 -----------------
 
-The following are some of the methods supported by the  {+driver-long+}
-implementation of LINQ:
+The following are some methods supported by the {+driver-long+} implementation of LINQ:
 
 .. list-table::
    :header-rows: 1
@@ -801,6 +800,9 @@ implementation of LINQ:
    * - ``LongCount``
      - Returns an ``Int64`` that represents the number of documents that match the specified criteria
 
+   * - ``DateFromString``
+     - Converts a ``string`` to a ``DateTime`` object
+
    * - ``Distinct``
      - Returns distinct documents that match the specified criteria