Revert accidental Storybook upgrade (#40)

package.json

@@ -21,14 +21,14 @@
     "@babel/core": "7.9.0",
     "@babel/preset-react": "7.9.4",
     "@babel/runtime-corejs3": "7.9.2",
-    "@storybook/addon-actions": "6.2.5",
-    "@storybook/addon-knobs": "6.2.5",
-    "@storybook/addon-links": "6.2.5",
-    "@storybook/addons": "6.2.5",
-    "@storybook/components": "6.2.5",
-    "@storybook/core-events": "6.2.5",
-    "@storybook/preact": "6.2.5",
-    "@storybook/theming": "6.2.5",
+    "@storybook/addon-actions": "5.3.21",
+    "@storybook/addon-knobs": "5.3.21",
+    "@storybook/addon-links": "5.3.21",
+    "@storybook/addons": "5.3.21",
+    "@storybook/components": "5.3.21",
+    "@storybook/core-events": "5.3.21",
+    "@storybook/preact": "5.3.21",
+    "@storybook/theming": "5.3.21",
     "@types/react": "16.8.8",
     "@types/webpack-env": "1.13.9",
     "babel-loader": "8.0.6",
@@ -37,9 +37,9 @@
     "typescript": "4.2.3"
   },
   "peerDependencies": {
-    "@storybook/addons": "^6.0.0",
-    "@storybook/components": "^6.0.0",
-    "@storybook/theming": "^6.0.0",
+    "@storybook/addons": "^5.0.0",
+    "@storybook/components": "^5.0.0",
+    "@storybook/theming": "^5.0.0",
     "react": ">=16.8.0"
   },
   "scripts": {
@@ -54,7 +54,7 @@
     "build-storybook": "build-storybook -s public -c test/.storybook"
   },
   "dependencies": {
-    "@storybook/client-api": "6.2.5",
+    "@storybook/client-api": "5.3.21",
     "@types/styled-jsx": "2.2.8",
     "preact": "10.4.1",
     "preact-render-to-string": "5.1.7",