fix: Import Transition directly to fix rollup warning

package.json

@@ -31,16 +31,17 @@
     "lodash": "^4.17.11",
     "popper.js": "^1.14.4",
     "react-portal": "^4.1.5",
-    "react-transition-group": "^2.5.0",
-    "styled-system": "^3.1.11"
-  },
-  "peerDependencies": {
+    "styled-system": "^3.1.11",
     "polished": "^2.0.0",
     "prop-types": "^15.6.1",
-    "react": "^16.2.0",
     "react-animations": "^1.0.0",
+    "react-transition-group": "^2.5.0",
     "styled-components": "^4.0.0"
   },
+  "peerDependencies": {
+    "react": "^16.5.0",
+    "react-dom": "^16.5.0"
+  },
   "devDependencies": {
     "@babel/core": "^7.1.2",
     "@babel/plugin-proposal-class-properties": "^7.1.0",
@@ -61,10 +62,7 @@
     "jest": "^23.6.0",
     "jest-styled-components": "^6.2.1",
     "npm-run-all": "^4.1.2",
-    "polished": "^2.2.0",
-    "prop-types": "^15.6.1",
     "react": "^16.5.2",
-    "react-animations": "^1.0.0",
     "react-dom": "^16.5.2",
     "react-router-dom": "^4.2.2",
     "react-test-renderer": "^16.5.2",

src/Collapse/Collapse.js

@@ -1,7 +1,7 @@
 import React, { Component } from 'react';
 import PropTypes from 'prop-types';
 import { css } from 'styled-components';
-import Transition from 'react-transition-group/Transition';
+import { Transition } from 'react-transition-group';
 import { createComponent } from '../utils';
 
 const getTransitionStyle = (state, duration) => {