Bump rxjs from 7.2.0 to 7.4.0 in /app

Bumps [rxjs](https://github.com/reactivex/rxjs) from 7.2.0 to 7.4.0.
- [Release notes](https://github.com/reactivex/rxjs/releases)
- [Changelog](https://github.com/ReactiveX/rxjs/blob/master/CHANGELOG.md)
- [Commits](https://github.com/reactivex/rxjs/compare/7.2.0...7.4.0)

---
updated-dependencies:
- dependency-name: rxjs
  dependency-type: direct:production
  update-type: version-update:semver-minor
...
Signed-off-by: Ndependabot[bot] <support@github.com>

app/package.json

@@ -29,7 +29,7 @@
     "mz": "^2.7.0",
     "native-process-working-directory": "^1.0.2",
     "npm": "6",
-    "rxjs": "^7.2.0",
+    "rxjs": "^7.4.0",
     "source-map-support": "^0.5.20",
     "v8-compile-cache": "^2.3.0",
     "yargs": "^17.1.0"

app/yarn.lock

@@ -3046,10 +3046,10 @@ run-queue@^1.0.0, run-queue@^1.0.3:
   dependencies:
     aproba "^1.1.1"
 
-rxjs@^7.2.0:
-  version "7.2.0"
-  resolved "https://registry.yarnpkg.com/rxjs/-/rxjs-7.2.0.tgz#5cd12409639e9514a71c9f5f9192b2c4ae94de31"
-  integrity sha512-aX8w9OpKrQmiPKfT1bqETtUr9JygIz6GZ+gql8v7CijClsP0laoFUdKzxFAoWuRdSlOdU2+crss+cMf+cqMTnw==
+rxjs@^7.4.0:
+  version "7.4.0"
+  resolved "https://registry.yarnpkg.com/rxjs/-/rxjs-7.4.0.tgz#a12a44d7eebf016f5ff2441b87f28c9a51cebc68"
+  integrity sha512-7SQDi7xeTMCJpqViXh8gL/lebcwlp3d831F05+9B44A4B0WfsEwUQHR64gsH1kvJ+Ep/J9K2+n1hVl1CsGN23w==
   dependencies:
     tslib "~2.1.0"