CSHARP-2392: Minor change to tests.

Author: rstam

README.md

@@ -117,6 +117,7 @@ Please see our [guidelines](CONTRIBUTING.md) for contributing to the driver.
 * Dow Liu                   [email protected]
 * Chuck Lu                  https://github.com/chucklu
 * Alex Lyman                [email protected]
+* John Murphy               https://github.com/jsmurphy
 * Alexander Nagy            [email protected]
 * Sridhar Nanjundeswaran    https://github.com/sridharn
 * Rich Quackenbush          [email protected]

tests/MongoDB.Driver.Core.Tests/ChangeStreamDocumentTests.cs

@@ -72,10 +72,12 @@ public void BackingDocument_should_return_expected_result()
             result.Should().BeSameAs(backingDocument);
         }
 
-        [Fact]
-        public void ClusterTime_should_return_expected_result()
+        [Theory]
+        [InlineData(1, 2)]
+        [InlineData(3, 4)]
+        public void ClusterTime_should_return_expected_result(int timestamp, int increment)
         {
-            var value = new BsonTimestamp(DateTime.Now.Ticks);
+            var value = new BsonTimestamp(timestamp, increment);
             var backingDocument = new BsonDocument { { "other", 1 }, { "clusterTime", value } };
             var subject = CreateSubject(backingDocument: backingDocument);