[Snyk] Fix for 4 vulnerabilities

[epfable]

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

Snyk has created this PR to fix one or more vulnerable packages in the `rubygems` dependencies of this project.

#### Changes included in this PR - 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. ```

#### Vulnerabilities that will be fixed ##### With an upgrade: Severity | Priority Score (*) | Issue | Breaking Change | Exploit Maturity :-------------------------:|-------------------------|:-------------------------|:-------------------------|:-------------------------  | **524/1000**
**Why?** Has a fix available, CVSS 6.2 | Use After Free
[SNYK-RUBY-NOKOGIRI-6228056](https://snyk.io/vuln/SNYK-RUBY-NOKOGIRI-6228056) | No | No Known Exploit  | **479/1000**
**Why?** Has a fix available, CVSS 5.3 | Regular Expression Denial of Service (ReDoS)
[SNYK-RUBY-RACK-6274383](https://snyk.io/vuln/SNYK-RUBY-RACK-6274383) | No | No Known Exploit  | **479/1000**
**Why?** Has a fix available, CVSS 5.3 | Regular Expression Denial of Service (ReDoS)
[SNYK-RUBY-RACK-6274384](https://snyk.io/vuln/SNYK-RUBY-RACK-6274384) | No | No Known Exploit  | **589/1000**
**Why?** Has a fix available, CVSS 7.5 | Denial of Service (DoS)
[SNYK-RUBY-RACK-6274385](https://snyk.io/vuln/SNYK-RUBY-RACK-6274385) | No | No Known Exploit (*) Note that the real score may have changed since the PR was raised. Check the changes in this PR to ensure they won't cause issues with your project. ------------ **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](https://app.snyk.io/org/caringmachine/project/ef473cfe-9121-4294-b887-efd8365f68f4?utm_source=github&utm_medium=referral&page=fix-pr) 🛠 [Adjust project settings](https://app.snyk.io/org/caringmachine/project/ef473cfe-9121-4294-b887-efd8365f68f4?utm_source=github&utm_medium=referral&page=fix-pr/settings) 📚 [Read more about Snyk's upgrade and patch logic](https://support.snyk.io/hc/en-us/articles/360003891078-Snyk-patches-to-fix-vulnerabilities) [//]: # (snyk:metadata:{"prId":"b787ccc2-8909-4885-bb3a-3c377910d70d","prPublicId":"b787ccc2-8909-4885-bb3a-3c377910d70d","dependencies":[{"name":"middleman","from":"4.2.1","to":"4.3.0"},{"name":"middleman-autoprefixer","from":"2.7.1","to":"2.8.0"},{"name":"middleman-syntax","from":"3.0.0","to":"3.2.0"},{"name":"nokogiri","from":"1.8.5","to":"1.15.6"}],"packageManager":"rubygems","projectPublicId":"ef473cfe-9121-4294-b887-efd8365f68f4","projectUrl":"https://app.snyk.io/org/caringmachine/project/ef473cfe-9121-4294-b887-efd8365f68f4?utm_source=github&utm_medium=referral&page=fix-pr","type":"auto","patch":[],"vulns":["SNYK-RUBY-NOKOGIRI-6228056","SNYK-RUBY-RACK-6274383","SNYK-RUBY-RACK-6274384","SNYK-RUBY-RACK-6274385"],"upgrade":["SNYK-RUBY-NOKOGIRI-6228056","SNYK-RUBY-RACK-6274383","SNYK-RUBY-RACK-6274384","SNYK-RUBY-RACK-6274385"],"isBreakingChange":false,"env":"prod","prType":"fix","templateVariants":["pr-warning-shown","priorityScore"],"priorityScoreList":[524,479,479,589],"remediationStrategy":"vuln"}) --- **Learn how to fix vulnerabilities with free interactive lessons:** 🦉 [Use After Free](https://learn.snyk.io/lesson/use-after-free/?loc=fix-pr) 🦉 [Regular Expression Denial of Service (ReDoS)](https://learn.snyk.io/lesson/redos/?loc=fix-pr)