deps: bump it-drain from 1.0.5 to 2.0.0 (libp2p#390)

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

package.json

@@ -162,7 +162,7 @@
     "hashlru": "^2.3.0",
     "interface-datastore": "^7.0.0",
     "it-all": "^1.0.6",
-    "it-drain": "^1.0.5",
+    "it-drain": "^2.0.0",
     "it-first": "^1.0.6",
     "it-length": "^1.0.3",
     "it-length-prefixed": "^8.0.2",