all: enable race detection

Change-Id: I4c1018048e34898aee4ec1c040395b6bc7eccd4c
Reviewed-on: https://cue-review.googlesource.com/c/cue/+/2288
Reviewed-by: Marcel van Lohuizen <mpvl@google.com>
diff --git a/cloudbuild.yaml b/cloudbuild.yaml
index 1eb37e4..54158fa 100644
--- a/cloudbuild.yaml
+++ b/cloudbuild.yaml
@@ -1,4 +1,4 @@
 steps:
 - name: golang:1.12
   env: ['GO111MODULE=on']
-  args: ['go', 'test', './...']
\ No newline at end of file
+  args: ['go', 'test', './...', '-race' ]