chore(deps): update dependency c8 to v10

Author: renovate-bot

package.json

@@ -38,7 +38,7 @@
   "devDependencies": {
     "@grpc/proto-loader": "^0.7.0",
     "@google-cloud/spanner": "^6.0.0",
-    "c8": "^7.7.2",
+    "c8": "^10.0.0",
     "google-auth-library": "^8.0.0",
     "google-gax": "^3.0.0",
     "google-protobuf": "^3.17.1",