chore(deps): update dependency node-pre-gyp to v0.15.0 (open-telemetry#1158)

Author: renovate-bot

Diff for: packages/opentelemetry-plugin-grpc/package.json

@@ -54,7 +54,7 @@
     "grpc": "1.24.3",
     "gts": "2.0.2",
     "mocha": "7.2.0",
-    "node-pre-gyp": "0.12.0",
+    "node-pre-gyp": "0.15.0",
     "nyc": "15.1.0",
     "rimraf": "3.0.2",
     "semver": "7.3.2",