chore(deps): update dependency @lit-labs/observers to v2.1.0 (#4016)

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

Author: renovate[bot]

packages/elements/package.json

@@ -46,7 +46,7 @@
   },
   "homepage": "https://github.com/stryker-mutator/mutation-testing-elements/tree/master/packages/elements#readme",
   "devDependencies": {
-    "@lit-labs/observers": "2.0.6",
+    "@lit-labs/observers": "2.1.0",
     "@playwright/test": "1.57.0",
     "@stryker-mutator/core": "catalog:",
     "@stryker-mutator/typescript-checker": "catalog:",