chore(package): update bn.js to version 5.1.2

Author: greenkeeper[bot]

package.json

@@ -26,7 +26,7 @@
   "dependencies": {
     "bencode": "^2.0.1",
     "bittorrent-peerid": "^1.3.2",
-    "bn.js": "^5.1.1",
+    "bn.js": "^5.1.2",
     "chrome-dgram": "^3.0.4",
     "compact2string": "^1.4.1",
     "debug": "^4.1.1",