fix(deps): update dependency notistack to v0.9.4

Author: renovate-bot

package-lock.json

@@ -22,7 +22,7 @@
     "jscpd-badge-reporter": "1.1.3",
     "ky": "0.15.0",
     "mixin-deep": "2.0.1",
-    "notistack": "0.9.3",
+    "notistack": "0.9.4",
     "pre-commit": "1.2.2",
     "ramda": "0.26.1",
     "react": "16.10.2",