Bump svelte from 2.13.5 to 2.15.0

Bumps [svelte](https://github.com/sveltejs/svelte) from 2.13.5 to 2.15.0.
- [Release notes](https://github.com/sveltejs/svelte/releases)
- [Changelog](https://github.com/sveltejs/svelte/blob/master/CHANGELOG.md)
- [Commits](https://github.com/sveltejs/svelte/compare/v2.13.5...v2.15.0)

Signed-off-by: dependabot[bot] <support@dependabot.com>

package-lock.json

@@ -379,9 +379,9 @@
       "dev": true
     },
     "svelte": {
-      "version": "2.13.5",
-      "resolved": "https://registry.npmjs.org/svelte/-/svelte-2.13.5.tgz",
-      "integrity": "sha512-Mg4+vRwAT1IMR4FAH3cOmMaVVrJ35xUI1qsTW+WoJvRpeBDx7aLZUbgBXnctxdfEJQ4BuP2MCuhYKy8917Au1A==",
+      "version": "2.15.0",
+      "resolved": "https://registry.npmjs.org/svelte/-/svelte-2.15.0.tgz",
+      "integrity": "sha512-rSrDbOftOHfPN8Epy8FHFUfr7L1WaZZBUC1UloNNH7+S7QHPyvbQw1KdrhtVYSuOslpjHe20xgTDR/tZn/sDMg==",
       "dev": true
     }
   }

package.json

@@ -2,6 +2,6 @@
   "devDependencies": {
     "rollup": "^0.66.4",
     "rollup-plugin-svelte": "^4.3.2",
-    "svelte": "^2.13.5"
+    "svelte": "^2.15.0"
   }
 }