Bump async from 2.6.1 to 2.6.4

Bumps [async](https://github.com/caolan/async) from 2.6.1 to 2.6.4.
- [Release notes](https://github.com/caolan/async/releases)
- [Changelog](https://github.com/caolan/async/blob/v2.6.4/CHANGELOG.md)
- [Commits](caolan/async@v2.6.1...v2.6.4)

---
updated-dependencies:
- dependency-name: async
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

package-lock.json

@@ -26,7 +26,7 @@
     "url": "https://github.com/joeferner/node-java.git"
   },
   "dependencies": {
-    "async": "2.6.1",
+    "async": "2.6.4",
     "find-java-home": "1.1.0",
     "glob": "7.1.6",
     "lodash": "^4.17.21",