Increase default timeout for long running tests.

Change-Id: I17bc1aaeebb3968f63c58164129b4f0f35c06c19
diff --git a/cmake/vec_cc_test.cmake b/cmake/vec_cc_test.cmake
index d7d5951..83e03b2 100644
--- a/cmake/vec_cc_test.cmake
+++ b/cmake/vec_cc_test.cmake
@@ -28,7 +28,7 @@
 )
 
 if("${_RULE_TIMEOUT}" STREQUAL "")
-  set(_TIMEOUT 20)
+  set(_TIMEOUT 30)
 else()
   set(_TIMEOUT ${_RULE_TIMEOUT})
 endif()