Switch to npx instead of digging into npm bin location

.circleci/build-and-publish-docs.sh

@@ -62,7 +62,7 @@ echo "Done generating documentation output"
 echo 'STARTING PUBLISH'
 
 # WILL ALWAYS FAIL IF INITIATED FROM PR BRANCH
-./node_modules/.bin/gh-pages \
+npx gh-pages \
   --silent \
   --repo https://$GITHUB_TOKEN@github.com/OHIF/Viewers.git \
   --message 'Autogenerated Message: [ci skip]' \

.circleci/config.yml

@@ -284,7 +284,8 @@ jobs:
           name: Build and push Docker image
           command: |
             # This file will exist if a new version was published by
-            # our `semantic-release` command in the previous job
+            # our command in the previous job. Created in npm postpublish hook
+            # in the `platform/viewer` project.
             if [[ ! -e platform/viewer/success_version.txt ]]; then
               exit 0
             else