chore:(deps): bump rxjs from 6.6.3 to 6.6.6

Bumps [rxjs](https://github.com/reactivex/rxjs) from 6.6.3 to 6.6.6.
- [Release notes](https://github.com/reactivex/rxjs/releases)
- [Changelog](https://github.com/ReactiveX/rxjs/blob/6.6.6/CHANGELOG.md)
- [Commits](ReactiveX/rxjs@6.6.3...6.6.6)

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

Author: dependabot[bot]

package-lock.json

@@ -61,7 +61,7 @@
     "graphql-tag": "^2.12.0",
     "iso8601-duration": "^1.3.0",
     "lodash-es": "^4.17.20",
-    "rxjs": "~6.6.3",
+    "rxjs": "~6.6.6",
     "tslib": "^2.1.0",
     "uuid": "^8.3.2",
     "zone.js": "^0.10.3"