deps: update dependency @google-cloud/spanner to v8 (GoogleCloudPlatform#3293)

Author: renovate-bot

benchmarks/latency-comparison/nodejs/package.json

@@ -9,7 +9,7 @@
     "typescript": "^5.4.5"
   },
   "dependencies": {
-    "@google-cloud/spanner": "^7.8.0",
+    "@google-cloud/spanner": "^8.0.0",
     "@types/pg": "^8.11.6",
     "dotenv": "^16.4.5",
     "pg": "^8.11.3",

benchmarks/nodejs/package.json

@@ -10,7 +10,7 @@
   "author": "",
   "license": "ISC",
   "dependencies": {
-    "@google-cloud/spanner": "^7.0.0",
+    "@google-cloud/spanner": "^8.0.0",
     "pg": "^8.8.0"
   }
 }