Add vuepress dist directory to .gitignore

Keep the files generated when running the build script from being
tracked in the repository.

Signed-off-by: Derick Montague <derick.montague@ibm.com>
Change-Id: I3ee9466cf2a7becffd442b81b47e0d073a2a7128
diff --git a/.gitignore b/.gitignore
index b725e4a..df0df9b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,6 +1,7 @@
 .DS_Store
 node_modules
 /dist
+/docs/.vuepress/dist
 
 # local env files
 .env.local