Fix contributing readme typo

Correct npm run docs:serve for running vue press docs

Signed-off-by: Dixsie Wolmers <dixsie@ibm.com>
Change-Id: Idd2e54f3f61e06baf46121984e0907989a0f3801
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 85ca6e3..ec9d2b8 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -46,7 +46,7 @@
 
 ### Run Documentation Locally (Vuepress static site generation)
 ```
-Run npm docs:serve
+npm run docs:serve
 ```
 
 ### Run unit tests