Switch to istanbul for code coverage (#57)

Author: Demivan

package.json

@@ -72,7 +72,7 @@
     "@release-it-plugins/lerna-changelog": "6.0.0",
     "@types/node": "18.15.5",
     "@vitejs/plugin-vue": "4.1.0",
-    "@vitest/coverage-c8": "0.29.7",
+    "@vitest/coverage-istanbul": "^0.34.1",
     "@vue/compiler-sfc": "3.2.47",
     "dotenv-cli": "7.1.0",
     "eslint": "8.36.0",
@@ -84,7 +84,7 @@
     "tsup": "7.2.0",
     "typescript": "5.0.2",
     "vite": "4.2.1",
-    "vitest": "0.29.7",
+    "vitest": "0.34.1",
     "vue": "3.2.47",
     "vue-loader": "17.0.1",
     "webpack": "5.76.2"