Bump resolve-url-loader from 3.1.4 to 5.0.0 in /idp

Bumps [resolve-url-loader](https://github.com/bholloway/resolve-url-loader/tree/HEAD/packages/resolve-url-loader) from 3.1.4 to 5.0.0.
- [Release notes](https://github.com/bholloway/resolve-url-loader/releases)
- [Changelog](https://github.com/bholloway/resolve-url-loader/blob/v5/packages/resolve-url-loader/CHANGELOG.md)
- [Commits](https://github.com/bholloway/resolve-url-loader/commits/5.0.0/packages/resolve-url-loader)

---
updated-dependencies:
- dependency-name: resolve-url-loader
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

idp/package.json

@@ -138,7 +138,7 @@
     "react-intl-cra": "^0.3.3",
     "react-intl-po": "^2.2.2",
     "resolve": "1.20.0",
-    "resolve-url-loader": "^3.1.2",
+    "resolve-url-loader": "^5.0.0",
     "sass-loader": "11.0.1",
     "source-map-explorer": "^2.5.2",
     "style-loader": "2.0.0",