Uninstall stream-chain dependency

Author: robertbrignull

extensions/ql-vscode/package-lock.json

@@ -1765,7 +1765,6 @@
     "semver": "^7.5.2",
     "source-map": "^0.7.4",
     "source-map-support": "^0.5.21",
-    "stream-chain": "^2.2.4",
     "stream-json": "^1.7.3",
     "styled-components": "^6.0.2",
     "tmp": "^0.1.0",