Bump koa from 2.15.0 to 2.15.4 (#2457)

Bumps [koa](https://github.com/koajs/koa) from 2.15.0 to 2.15.4.
- [Release notes](https://github.com/koajs/koa/releases)
- [Changelog](https://github.com/koajs/koa/blob/2.15.4/History.md)
- [Commits](https://github.com/koajs/koa/compare/2.15.0...2.15.4)

---
updated-dependencies:
- dependency-name: koa
  dependency-type: indirect
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

package-lock.json

@@ -8918,9 +8918,10 @@
       }
     },
     "node_modules/koa": {
-      "version": "2.15.0",
-      "resolved": "https://registry.npmjs.org/koa/-/koa-2.15.0.tgz",
-      "integrity": "sha512-KEL/vU1knsoUvfP4MC4/GthpQrY/p6dzwaaGI6Rt4NQuFqkw3qrvsdYF5pz3wOfi7IGTvMPHC9aZIcUKYFNxsw==",
+      "version": "2.15.4",
+      "resolved": "https://registry.npmjs.org/koa/-/koa-2.15.4.tgz",
+      "integrity": "sha512-7fNBIdrU2PEgLljXoPWoyY4r1e+ToWCmzS/wwMPbUNs7X+5MMET1ObhJBlUkF5uZG9B6QhM2zS1TsH6adegkiQ==",
+      "license": "MIT",
       "dependencies": {
         "accepts": "^1.3.5",
         "cache-content-type": "^1.0.0",