fix(deps): update dependency is-plain-object to v3 (#361)

Author: renovate[bot]

package.json

@@ -79,7 +79,7 @@
     "react-dom": "^0.14.8 || ^15.0.1 || ^16.0.0"
   },
   "dependencies": {
-    "is-plain-object": "2.0.4",
+    "is-plain-object": "3.0.0",
     "stringify-object": "3.3.0"
   },
   "jest": {

yarn.lock

@@ -4076,7 +4076,13 @@ is-plain-obj@^1.1.0:
   version "1.1.0"
   resolved "https://registry.yarnpkg.com/is-plain-obj/-/is-plain-obj-1.1.0.tgz#71a50c8429dfca773c92a390a4a03b39fcd51d3e"
 
-is-plain-object@2.0.4, is-plain-object@^2.0.1, is-plain-object@^2.0.3, is-plain-object@^2.0.4:
+is-plain-object@3.0.0:
+  version "3.0.0"
+  resolved "https://registry.yarnpkg.com/is-plain-object/-/is-plain-object-3.0.0.tgz#47bfc5da1b5d50d64110806c199359482e75a928"
+  dependencies:
+    isobject "^4.0.0"
+
+is-plain-object@^2.0.1, is-plain-object@^2.0.3, is-plain-object@^2.0.4:
   version "2.0.4"
   resolved "https://registry.yarnpkg.com/is-plain-object/-/is-plain-object-2.0.4.tgz#2c163b3fafb1b606d9d17928f05c2a1c38e07677"
   dependencies:
@@ -4206,6 +4212,10 @@ isobject@^3.0.0, isobject@^3.0.1:
   version "3.0.1"
   resolved "https://registry.yarnpkg.com/isobject/-/isobject-3.0.1.tgz#4e431e92b11a9731636aa1f9c8d1ccbcfdab78df"
 
+isobject@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/isobject/-/isobject-4.0.0.tgz#3f1c9155e73b192022a80819bacd0343711697b0"
+
 isstream@~0.1.2:
   version "0.1.2"
   resolved "https://registry.yarnpkg.com/isstream/-/isstream-0.1.2.tgz#47e63f7af55afa6f92e1500e690eb8b8529c099a"