Replace single-line null check with null-conditional

Author: edwardneal

src/Microsoft.Data.SqlClient/netcore/src/Microsoft/Data/SqlClient/SqlConnection.cs

@@ -2350,8 +2350,7 @@ private static void ChangePassword(string connectionString, SqlConnectionString
             }
             finally
             {
-                if (con != null)
-                    con.Dispose();
+                con?.Dispose();
             }
             SqlConnectionPoolKey key = new SqlConnectionPoolKey(connectionString, credential, accessToken: null, accessTokenCallback: null);
 

src/Microsoft.Data.SqlClient/netfx/src/Microsoft/Data/SqlClient/SqlConnection.cs

@@ -2521,8 +2521,7 @@ private static void ChangePassword(string connectionString, SqlConnectionString
             }
             finally
             {
-                if (con != null)
-                    con.Dispose();
+                con?.Dispose();
             }
             SqlConnectionPoolKey key = new SqlConnectionPoolKey(connectionString, credential, accessToken: null, accessTokenCallback: null);