Merged PR 802784: Remove unused code

Cleaning up some old pinvoke code

Public/Src/Engine/UnitTests/Processes/ProcessDumperTests.cs

@@ -173,12 +173,6 @@ namespace Test.BuildXL.Processes
             }
         }
 
-        /// <summary>
-        /// Sends a signal to a processes identified by pid
-        /// </summary>
-        [DllImport("libc", SetLastError = true, EntryPoint = "kill")]
-        private static extern unsafe int SendSignal(int pid, int signal);
-
         /// <summary>
         /// Exception for test failure that allows test to be retried
         /// </summary>