internal/kokoro: fix CI pathing (#503)

diff --git a/internal/kokoro/test.sh b/internal/kokoro/test.sh
index c49698c..84663c2 100755
--- a/internal/kokoro/test.sh
+++ b/internal/kokoro/test.sh
@@ -13,7 +13,7 @@
 set -x
 
 # cd to project dir on Kokoro instance
-cd git/google_api
+cd github/google-api-go-client
 
 go version