[Snyk] Fix for 1 vulnerabilities

Changes to the following files to upgrade the vulnerable dependencies to a fixed version:
- Gemfile

⚠️ Warning

``` Failed to update the Gemfile.lock, please update manually before merging. ```

Severity	Priority Score (*)	Issue	Breaking Change	Exploit Maturity
	776/1000 Why? Recently disclosed, Has a fix available, CVSS 9.8	Remote Code Execution (RCE) SNYK-RUBY-RAILS-2948997	No	No Known Exploit

(*) Note that the real score may have changed since the PR was raised.

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