Fixed variable name for github token

user-doc/go-spelling

@@ -63,14 +63,14 @@ if test -z $TRAVIS ; then
 # If not a pull request add a comment on the commit message
 elif [ $TRAVIS_PULL_REQUEST=="false" ] ; then
     ASPELL_RESULTS=`cat spelling_results`
-    curl -i -H "Authorization: token $GITHUB_TOKEN" \
+    curl -i -H "Authorization: token $GIT_TOKEN" \
     -H "Content-Type: application/json" \
     -X POST -d "{\"body\":\"$ASPELL_RESULTS\"}" \
     https://api.github.com/repos/plumed/plumed2/commits/$TRAVIS_COMMIT/comments
 # If it is a pull request comment on the pull request
 else
     ASPELL_RESULTS=`cat spelling_results`
-    curl -i -H "Authorization: token $GITHUB_TOKEN" \
+    curl -i -H "Authorization: token $GIT_TOKEN" \
     -H "Content-Type: application/json" \
     -X POST -d "{\"body\":\"$ASPELL_RESULTS\"}" \
     https://api.github.com/repos/plumed/plumed2/issues/$TRAVIS_PULL_REQUEST/comments