Bump rxjs from 6.6.2 to 6.6.3

Bumps [rxjs](https://github.com/reactivex/rxjs) from 6.6.2 to 6.6.3.
- [Release notes](https://github.com/reactivex/rxjs/releases)
- [Changelog](https://github.com/ReactiveX/rxjs/blob/6.6.3/CHANGELOG.md)
- [Commits](ReactiveX/rxjs@6.6.2...6.6.3)

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

package.json

@@ -99,7 +99,7 @@
     "ngx-monaco-editor": "8.1.1",
     "pdfjs-dist": "2.5.207",
     "raphael": "2.3.0",
-    "rxjs": "^6.6.2",
+    "rxjs": "^6.6.3",
     "snyk": "^1.404.0",
     "tslib": "^2.0.1",
     "zone.js": "~0.10.2"