Bump net-imap from 0.6.4 to 0.6.4.1 (#2461)

Bumps [net-imap](https://github.com/ruby/net-imap) from 0.6.4 to 0.6.4.1.
- [Release notes](https://github.com/ruby/net-imap/releases)
- [Commits](ruby/net-imap@v0.6.4...v0.6.4.1)

---
updated-dependencies:
- dependency-name: net-imap
  dependency-version: 0.6.4.1
  dependency-type: indirect
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

Gemfile.lock

@@ -299,7 +299,7 @@ GEM
     mustermann (3.1.0)
     net-http (0.9.1)
       uri (>= 0.11.1)
-    net-imap (0.6.4)
+    net-imap (0.6.4.1)
       date
       net-protocol
     net-pop (0.1.2)