chore(deps): update dependency sinon to v20

Author: renovate[bot]

packages/lit-override/package.json

@@ -68,7 +68,7 @@
     "lit-html": "3.3.0",
     "playwright": "1.52.0",
     "rimraf": "5.0.10",
-    "sinon": "17.0.1",
+    "sinon": "20.0.0",
     "tsconfig-config": "workspace:*",
     "tslib": "2.8.1",
     "tsup": "8.4.0",