Bump mailgun-ruby from 1.4.3 to 1.4.4

Bumps [mailgun-ruby](https://github.com/mailgun/mailgun-ruby) from 1.4.3 to 1.4.4.
- [Release notes](https://github.com/mailgun/mailgun-ruby/releases)
- [Changelog](https://github.com/mailgun/mailgun-ruby/blob/master/CHANGELOG.md)
- [Commits](mailgun/mailgun-ruby@v1.4.3...v1.4.4)

---
updated-dependencies:
- dependency-name: mailgun-ruby
  dependency-version: 1.4.4
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

Gemfile.lock

@@ -275,7 +275,7 @@ GEM
       net-imap
       net-pop
       net-smtp
-    mailgun-ruby (1.4.3)
+    mailgun-ruby (1.4.4)
       faraday (~> 2.1)
       faraday-multipart (< 2)
       mini_mime
@@ -578,7 +578,7 @@ GEM
     websocket-extensions (0.1.5)
     xpath (3.2.0)
       nokogiri (~> 1.8)
-    zeitwerk (2.7.5)
+    zeitwerk (2.8.2)
 
 PLATFORMS
   aarch64-linux