[Snyk] Security upgrade ruby from 2.6.0 to 2.6.6

[snyk-bot]

Keeping your Docker base image up-to-date means you’ll benefit from security fixes in the latest version of your chosen image.

Changes included in this PR

• app/Dockerfile

We recommend upgrading to ruby:2.6.6, as this image has only 302 known vulnerabilities. To do this, merge this pull request, then verify your application still works as expected.

Some of the most important vulnerabilities in your base image include:

Severity	Priority Score / 1000	Issue	Exploit Maturity
	714	Integer Overflow or Wraparound SNYK-DEBIAN9-PERL-570790	No Known Exploit
	714	Buffer Overflow SNYK-DEBIAN9-PERL-570794	No Known Exploit
	714	Out-of-bounds Write SNYK-DEBIAN9-PERL-570799	No Known Exploit
	714	Out-of-bounds Write SNYK-DEBIAN9-UNZIP-358298	No Known Exploit
	714	Out-of-bounds Write SNYK-DEBIAN9-WGET-342192	No Known Exploit

---

Note: You are seeing this because you or someone else with access to this repository has authorized Snyk to open fix PRs.

For more information:
🧐 View latest project report

🛠 Adjust project settings