chore(deps): update storybook monorepo to v7.6.15 (#5317)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

webview/package.json

@@ -39,11 +39,11 @@
     "vega-util": "1.17.2"
   },
   "devDependencies": {
-    "@storybook/addons": "7.6.14",
-    "@storybook/builder-webpack5": "7.6.14",
+    "@storybook/addons": "7.6.15",
+    "@storybook/builder-webpack5": "7.6.15",
     "@storybook/preset-scss": "1.0.3",
-    "@storybook/react": "7.6.14",
-    "@storybook/react-webpack5": "7.6.14",
+    "@storybook/react": "7.6.15",
+    "@storybook/react-webpack5": "7.6.15",
     "@storybook/testing-library": "0.2.2",
     "@svgr/core": "^8.0.0",
     "@svgr/plugin-jsx": "^8.0.1",
@@ -73,7 +73,7 @@
     "raw-loader": "4.0.2",
     "sass": "1.70.0",
     "sass-loader": "13.3.3",
-    "storybook": "7.6.14",
+    "storybook": "7.6.15",
     "storybook-addon-themes": "6.1.0",
     "style-loader": "3.3.4",
     "stylelint": "15.11.0",