Bump net-imap from 0.6.4 to 0.6.4.1

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
...

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

Author: dependabot[bot]

Gemfile.lock

@@ -173,7 +173,7 @@ GEM
     minitest (5.25.5)
     minitest-stub_any_instance (1.0.3)
     msgpack (1.8.0)
-    net-imap (0.6.4)
+    net-imap (0.6.4.1)
       date
       net-protocol
     net-pop (0.1.2)