[Snyk] Upgrade rxjs from 6.6.3 to 6.6.7

This PR was automatically created by Snyk using the credentials of a real user.

Snyk has created this PR to upgrade rxjs from 6.6.3 to 6.6.7.

![merge advice](https://app.snyk.io/badges/merge-advice/?package_manager=npm&package_name=rxjs&from_version=6.6.3&to_version=6.6.7&pr_id=c2559a09-01cb-4908-b7b2-75b3d65a93ed&visibility=true&has_feature_flag=false) :information_source: Keep your dependencies up-to-date. This makes it easier to fix existing vulnerabilities and to more quickly identify and fix newly disclosed vulnerabilities when they affect your project.

- The recommended version is **3 versions** ahead of your current version. - The recommended version was released **a year ago**, on 2021-03-28.

Release notes

Package name: rxjs

6.6.7 - 2021-03-28
6.6.6 - 2021-02-25
6.6.4 - 2021-02-24
6.6.3 - 2020-09-06

from rxjs GitHub release notes

**Note:** *You are seeing this because you or someone else with access to this repository has authorized Snyk to open upgrade PRs.* For more information: 🧐 [View latest project report](https://app.snyk.io/org/alfbisneto/project/9e39ad31-a1e8-4f9e-965e-9b0b1f113835?utm_source=github&utm_medium=referral&page=upgrade-pr) 🛠 [Adjust upgrade PR settings](https://app.snyk.io/org/alfbisneto/project/9e39ad31-a1e8-4f9e-965e-9b0b1f113835/settings/integration?utm_source=github&utm_medium=referral&page=upgrade-pr) 🔕 [Ignore this dependency or unsubscribe from future upgrade PRs](https://app.snyk.io/org/alfbisneto/project/9e39ad31-a1e8-4f9e-965e-9b0b1f113835/settings/integration?pkg=rxjs&utm_source=github&utm_medium=referral&page=upgrade-pr#auto-dep-upgrades)

alfbisneto / juice-shop

[Snyk] Upgrade rxjs from 6.6.3 to 6.6.7 #5

Snyk has created this PR to upgrade rxjs from 6.6.3 to 6.6.7.