chore(deps): bump @babel packages and regenerate yarn.lock

This is an attempt to fix this issue with Node.js 12:
- storybookjs/storybook#10477
- nodejs/node#32852

package.json

@@ -50,16 +50,16 @@
     "coverage": "nyc --reporter=lcov --reporter=text-summary yarn test"
   },
   "dependencies": {
-    "@babel/core": "7.8.7",
-    "@babel/plugin-proposal-class-properties": "7.8.3",
-    "@babel/plugin-transform-runtime": "7.8.3",
-    "@babel/preset-env": "7.8.7",
-    "@babel/preset-flow": "7.8.3",
-    "@babel/preset-react": "7.8.3",
-    "@babel/register": "7.8.6",
+    "@babel/core": "7.10.2",
+    "@babel/plugin-proposal-class-properties": "7.10.1",
+    "@babel/plugin-transform-runtime": "7.10.1",
+    "@babel/preset-env": "7.10.2",
+    "@babel/preset-flow": "7.10.1",
+    "@babel/preset-react": "7.10.1",
+    "@babel/register": "7.10.1",
     "babel-eslint": "10.1.0",
-    "babel-loader": "8.0.6",
-    "babel-plugin-istanbul": "5.2.0",
+    "babel-loader": "8.1.0",
+    "babel-plugin-istanbul": "6.0.0",
     "codecov": "3.6.5",
     "colorette": "1.1.0",
     "eslint": "6.8.0",