Breaking: bump rocksdb from 4.x to 5.x

Ref https://github.com/Level/rocksdb/releases/tag/v5.0.0
Ref Level/community#98

Author: vweevers

package.json

@@ -18,7 +18,7 @@
   ],
   "dependencies": {
     "level-packager": "^6.0.0",
-    "rocksdb": "^4.0.0"
+    "rocksdb": "^5.1.0"
   },
   "devDependencies": {
     "dependency-check": "^3.3.0",