chore(deps): 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](https://github.com/ruby/net-imap/compare/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>

Gemfile.lock

@@ -108,7 +108,7 @@ GEM
       coffee-script-source
       execjs
     coffee-script-source (1.12.2)
-    concurrent-ruby (1.3.7)
+    concurrent-ruby (1.3.6)
     connection_pool (3.0.2)
     crack (1.0.0)
       bigdecimal
@@ -211,7 +211,7 @@ GEM
     mysql2 (0.5.6)
     net-http (0.4.1)
       uri
-    net-imap (0.6.4)
+    net-imap (0.6.4.1)
       date
       net-protocol
     net-pop (0.1.2)