fix(package): add 'prop-types' in 'dependencies'

Author: matteocng

package.json

@@ -38,6 +38,7 @@
   ],
   "dependencies": {
     "node-sass": "^4.5.3",
+    "prop-types": "^15.5.10",
     "react": "^15.5.4",
     "react-css-modules": "^4.0.5",
     "react-dom": "^15.5.4",

yarn.lock

@@ -1353,15 +1353,7 @@ cross-spawn@^3.0.0:
     lru-cache "^4.0.1"
     which "^1.2.9"
 
-cross-spawn@^5.0.1:
-  version "5.0.1"
-  resolved "https://registry.yarnpkg.com/cross-spawn/-/cross-spawn-5.0.1.tgz#a3bbb302db2297cbea3c04edf36941f4613aa399"
-  dependencies:
-    lru-cache "^4.0.1"
-    shebang-command "^1.2.0"
-    which "^1.2.9"
-
-cross-spawn@^5.1.0:
+cross-spawn@^5.0.1, cross-spawn@^5.1.0:
   version "5.1.0"
   resolved "https://registry.yarnpkg.com/cross-spawn/-/cross-spawn-5.1.0.tgz#e8bd0efee58fcff6f8f94510a0a554bbfa235449"
   dependencies:
@@ -3946,7 +3938,7 @@ promise@^7.1.1:
   dependencies:
     asap "~2.0.3"
 
-prop-types@^15.5.7, prop-types@^15.5.8, prop-types@~15.5.7:
+prop-types@^15.5.10, prop-types@^15.5.7, prop-types@^15.5.8, prop-types@~15.5.7:
   version "15.5.10"
   resolved "https://registry.yarnpkg.com/prop-types/-/prop-types-15.5.10.tgz#2797dfc3126182e3a95e3dfbb2e893ddd7456154"
   dependencies: