Bump acorn from 6.3.0 to 6.4.1 in /graphviz-rough#151

dependabot[bot] wants to merge 1 commit intomasternidi3/graphviz-java:masterfrom

dependabot/npm_and_yarn/graphviz-rough/acorn-6.4.1nidi3/graphviz-java:dependabot/npm_and_yarn/graphviz-rough/acorn-6.4.1Copy head branch name to clipboard