chore(deps): update dependency is-ci to v4

Author: renovate[bot]

package.json

@@ -25,7 +25,7 @@
     "eslint-plugin-prettier": "5.2.1",
     "execa": "5.1.1",
     "husky": "9.1.7",
-    "is-ci": "3.0.1",
+    "is-ci": "4.1.0",
     "vitest": "^2.1.0",
     "lint-staged": "15.3.0",
     "p-retry": "4.6.2",

packages/vscode/package.json

@@ -691,7 +691,7 @@
     "@vscode/vsce": "2.29.0",
     "esbuild": "^0.27.1",
     "glob": "8.1.0",
-    "is-ci": "3.0.1",
+    "is-ci": "4.1.0",
     "mocha": "10.8.2",
     "ovsx": "0.10.1",
     "pkg-types": "2.2.0",