chore(deps): update dependency rollup to v2.26.4

Author: renovate-bot

package-lock.json

@@ -86,7 +86,7 @@
     "remark-preset-lint-travi": "1.3.9",
     "remark-toc": "7.0.0",
     "remark-usage": "8.0.0",
-    "rollup": "2.26.3",
+    "rollup": "2.26.4",
     "rollup-plugin-babel": "4.4.0",
     "sinon": "9.0.3",
     "travis-lint": "1.0.0",