GoogleTest: Add missing test case for gtest_discover_tests failure

Discovery timeout test needs split out into two components:
- build
- test

Building the project should result in a failure due to the timeout
when executing gtest discovery as a post build step.

Likewise, if you ran CTest after this build failure,
we should *also* detect that the discovery_timeout_test has not been built
because no discovery_timeout_test[1]_tests.cmake has been created
due to the test discovery failure (caused by the timeout).

Tests/RunCMake/GoogleTest/GoogleTest-discovery-timeout-test-result.txt

@@ -0,0 +1 @@
+[^0]

Tests/RunCMake/GoogleTest/GoogleTest-discovery-timeout-test-stderr.txt

@@ -0,0 +1,2 @@
+Unable to find executable: discovery_timeout_test_NOT_BUILT
+Errors while running CTest

Tests/RunCMake/GoogleTest/GoogleTest-discovery-timeout-test-stdout.txt

@@ -0,0 +1,18 @@
+Test project .*GoogleTest-build
+[ \t]*Start [0-9]+: discovery_timeout_test_NOT_BUILT
+Could not find executable discovery_timeout_test_NOT_BUILT
+Looked in the following places:
+discovery_timeout_test_NOT_BUILT
+discovery_timeout_test_NOT_BUILT(\.exe)?
+Debug/discovery_timeout_test_NOT_BUILT
+Debug/discovery_timeout_test_NOT_BUILT(\.exe)?
+Debug/discovery_timeout_test_NOT_BUILT
+Debug/discovery_timeout_test_NOT_BUILT(\.exe)?
+[^\n]+discovery_timeout_test_NOT_BUILT +\.+\*\*\*Not Run +[0-9.]+ sec
++
+0% tests passed, 1 tests failed out of 1
++
+Total Test time \(real\) =   +[0-9.]+ sec
++
+The following tests FAILED:
+[^\n]+discovery_timeout_test_NOT_BUILT \(Not Run\)

Tests/RunCMake/GoogleTest/RunCMakeTest.cmake

@@ -27,7 +27,7 @@ function(run_GoogleTest)
   )
 
   set(RunCMake_TEST_OUTPUT_MERGE 1)
-  run_cmake_command(GoogleTest-discovery-timeout
+  run_cmake_command(GoogleTest-discovery-timeout-build
     ${CMAKE_COMMAND}
     --build .
     --config Debug
@@ -69,6 +69,13 @@ function(run_GoogleTest)
     -R property_timeout\\.case_with_discovery
     --no-label-summary
   )
+
+  run_cmake_command(GoogleTest-discovery-timeout-test
+    ${CMAKE_CTEST_COMMAND}
+    -C Debug
+    -R discovery_timeout_test
+    --no-label-summary
+  )
 endfunction()
 
 run_GoogleTest()