dependencies: bump rpc-request from 7.1.7 to 7.1.8

Bumps [rpc-request](https://github.com/vansergen/rpc-request) from 7.1.7 to 7.1.8.
- [Release notes](https://github.com/vansergen/rpc-request/releases)
- [Changelog](https://github.com/vansergen/rpc-request/blob/main/CHANGELOG.md)
- [Commits](vansergen/rpc-request@v7.1.7...v7.1.8)

---
updated-dependencies:
- dependency-name: rpc-request
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

package.json

@@ -55,7 +55,7 @@
   },
   "homepage": "https://github.com/vansergen/poloniex-node-api#readme",
   "dependencies": {
-    "rpc-request": "^7.1.7",
+    "rpc-request": "^7.1.8",
     "ws": "^8.14.2"
   },
   "peerDependencies": {