chore(deps): update dependency redis to v4

Author: renovate[bot]

packages/opencensus-instrumentation-redis/package-lock.json

@@ -41,14 +41,14 @@
   "devDependencies": {
     "@types/mocha": "7.0.1",
     "@types/node": "10.17.60",
-    "@types/redis": "2.8.10",
+    "@types/redis": "4.0.10",
     "@types/semver": "7.1.0",
     "@types/shimmer": "1.0.1",
     "codecov": "3.5.0",
     "gts": "1.0.0",
     "mocha": "7.1.0",
     "nyc": "14.0.0",
-    "redis": "2.8.0",
+    "redis": "4.6.5",
     "rimraf": "3.0.0",
     "ts-node": "8.0.3",
     "typescript": "3.9.10"