Bump rxjs from 7.5.4 to 7.5.5 in /samples/lib/spa-angular-client

Bumps [rxjs](https://github.com/reactivex/rxjs) from 7.5.4 to 7.5.5.
- [Release notes](https://github.com/reactivex/rxjs/releases)
- [Changelog](https://github.com/ReactiveX/rxjs/blob/master/CHANGELOG.md)
- [Commits](ReactiveX/rxjs@7.5.4...7.5.5)

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

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

Author: dependabot[bot]

samples/lib/spa-angular-client/package-lock.json

@@ -32,7 +32,7 @@
     "bootstrap": "^4.6.0",
     "bowser": "^2.11.0",
     "core-js": "^3.21.1",
-    "rxjs": "~7.5.4",
+    "rxjs": "~7.5.5",
     "tslib": "^2.3.1",
     "zone.js": "~0.11.4"
   },