chore(gatsby): update Redux to v4 (#8296)

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## Summary

Redux 4 has been released for a while. Shall we update the dependency?

I've already tested the change in my fork and nothing is breaking.

### Motivation

Redux 4 has updated its TypeScript bindings. Personally, I prefer the new version much.

Putting it aside, Redux 4 has es modules support and dropped its dependency on `lodash`. Hence, it can make the bundle smaller.

close #8265

packages/gatsby/package.json

@@ -99,7 +99,7 @@
     "react-dev-utils": "^4.2.1",
     "react-error-overlay": "^3.0.0",
     "react-hot-loader": "^4.1.0",
-    "redux": "^3.6.0",
+    "redux": "^4.0.0",
     "relay-compiler": "1.5.0",
     "request": "^2.85.0",
     "shallow-compare": "^1.2.2",

yarn.lock

@@ -12010,11 +12010,6 @@ lockfile@^1.0.4:
   dependencies:
     signal-exit "^3.0.2"
 
-lodash-es@^4.2.1:
-  version "4.17.11"
-  resolved "https://registry.yarnpkg.com/lodash-es/-/lodash-es-4.17.11.tgz#145ab4a7ac5c5e52a3531fb4f310255a152b4be0"
-  integrity sha512-DHb1ub+rMjjrxqlB3H56/6MXtm1lSksDp2rA2cNWjG8mlDUYFhUj3Di2Zn5IwSU87xLv8tNIQ7sSwE/YOX/D/Q==
-
 lodash-webpack-plugin@^0.11.5:
   version "0.11.5"
   resolved "https://registry.yarnpkg.com/lodash-webpack-plugin/-/lodash-webpack-plugin-0.11.5.tgz#c4bd064b4f561c3f823fa5982bdeb12c475390b9"
@@ -12369,7 +12364,7 @@ longest@^1.0.0, longest@^1.0.1:
   resolved "https://registry.yarnpkg.com/longest/-/longest-1.0.1.tgz#30a0b2da38f73770e8294a0d22e6625ed77d0097"
   integrity sha1-MKCy2jj3N3DoKUoNIuZiXtd9AJc=
 
-loose-envify@^1.0.0, loose-envify@^1.1.0, loose-envify@^1.3.1:
+loose-envify@^1.0.0, loose-envify@^1.1.0, loose-envify@^1.3.1, loose-envify@^1.4.0:
   version "1.4.0"
   resolved "https://registry.yarnpkg.com/loose-envify/-/loose-envify-1.4.0.tgz#71ee51fa7be4caec1a63839f7e682d8132d30caf"
   integrity sha512-lyuxPGr/Wfhrlem2CL/UcnUc1zcqKAImBDzukY7Y5F/yQiNdko6+fRLevlw1HgMySw7f611UIY408EtxRSoK3Q==
@@ -15957,15 +15952,13 @@ reduce@^1.0.1:
   dependencies:
     object-keys "~1.0.0"
 
-redux@^3.6.0:
-  version "3.7.2"
-  resolved "https://registry.yarnpkg.com/redux/-/redux-3.7.2.tgz#06b73123215901d25d065be342eb026bc1c8537b"
-  integrity sha512-pNqnf9q1hI5HHZRBkj3bAngGZW/JMCmexDlOxw4XagXY2o1327nHH54LoTjiPJ0gizoqPDRqWyX/00g0hD6w+A==
+redux@^4.0.0:
+  version "4.0.1"
+  resolved "https://registry.yarnpkg.com/redux/-/redux-4.0.1.tgz#436cae6cc40fbe4727689d7c8fae44808f1bfef5"
+  integrity sha512-R7bAtSkk7nY6O/OYMVR9RiBI+XghjF9rlbl5806HJbQph0LJVHZrU5oaO4q70eUKiqMRqm4y07KLTlMZ2BlVmg==
   dependencies:
-    lodash "^4.2.1"
-    lodash-es "^4.2.1"
-    loose-envify "^1.1.0"
-    symbol-observable "^1.0.3"
+    loose-envify "^1.4.0"
+    symbol-observable "^1.2.0"
 
 reflect-metadata@^0.1.2:
   version "0.1.12"
@@ -18184,7 +18177,7 @@ symbol-observable@1.0.1:
   resolved "https://registry.yarnpkg.com/symbol-observable/-/symbol-observable-1.0.1.tgz#8340fc4702c3122df5d22288f88283f513d3fdd4"
   integrity sha1-g0D8RwLDEi310iKI+IKD9RPT/dQ=
 
-symbol-observable@^1.0.3, symbol-observable@^1.1.0:
+symbol-observable@^1.1.0, symbol-observable@^1.2.0:
   version "1.2.0"
   resolved "https://registry.yarnpkg.com/symbol-observable/-/symbol-observable-1.2.0.tgz#c22688aed4eab3cdc2dfeacbb561660560a00804"
   integrity sha512-e900nM8RRtGhlV36KGEU9k65K3mPb1WV70OdjfxlG2EAuM1noi/E/BaW/uMhL7bPEssK8QV57vN3esixjUvcXQ==