cmake: unittest: add -t run support

Add support to run unit tests directly from `west build`, for
environments where `west build -t run-test` (which runs the binary under
valgrind) is inappropriate or unavailable (WSL).

`west build -t run` also has the muscle-memory advantage of being the
same target name as the `native_sim` boards.

Signed-off-by: Jordan Yates <jordan@embeint.com>

cmake/modules/unittest.cmake

@@ -162,6 +162,13 @@ if(VALGRIND_PROGRAM)
     )
 endif()
 
+add_custom_target(run
+  COMMAND
+  $<TARGET_FILE:testbinary>
+  DEPENDS testbinary
+  WORKING_DIRECTORY ${APPLICATION_BINARY_DIR}
+  )
+
 add_custom_target(run-test
   COMMAND
   ${VALGRIND} ${VALGRIND_FLAGS}