Update storybook monorepo to v5.3.21

Author: renovate-bot

package.json

@@ -22,12 +22,12 @@
     "@babel/core": "7.12.10",
     "@rollup/plugin-commonjs": "17.0.0",
     "@rollup/plugin-node-resolve": "11.0.0",
-    "@storybook/addon-actions": "5.3.19",
-    "@storybook/addon-links": "5.3.19",
-    "@storybook/addon-notes": "5.3.19",
-    "@storybook/addon-storysource": "5.3.19",
-    "@storybook/addons": "5.3.19",
-    "@storybook/svelte": "5.3.19",
+    "@storybook/addon-actions": "5.3.21",
+    "@storybook/addon-links": "5.3.21",
+    "@storybook/addon-notes": "5.3.21",
+    "@storybook/addon-storysource": "5.3.21",
+    "@storybook/addons": "5.3.21",
+    "@storybook/svelte": "5.3.21",
     "babel-loader": "8.2.2",
     "rollup": "2.16.1",
     "rollup-plugin-svelte": "7.0.0",