Bump koa-session from 5.12.3 to 5.13.1

Bumps [koa-session](https://github.com/koajs/session) from 5.12.3 to 5.13.1.
- [Release notes](https://github.com/koajs/session/releases)
- [Changelog](https://github.com/koajs/session/blob/master/History.md)
- [Commits](https://github.com/koajs/session/compare/5.12.3...5.13.1)

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

package.json

@@ -65,7 +65,7 @@
     "koa-logger": "~3.2.1",
     "koa-redis": "^4.0.1",
     "koa-router": "^8.0.6",
-    "koa-session": "^5.12.3",
+    "koa-session": "^5.13.1",
     "koa-static": "^5.0.0",
     "koa-views": "^6.2.1",
     "koa-websocket": "^6.0.0",