Bump net-imap from 0.4.17 to 0.4.19

Bumps [net-imap](https://github.com/ruby/net-imap) from 0.4.17 to 0.4.19.
- [Release notes](https://github.com/ruby/net-imap/releases)
- [Commits](https://github.com/ruby/net-imap/compare/v0.4.17...v0.4.19)

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

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

Gemfile.lock

@@ -399,7 +399,7 @@ GEM
       bigdecimal (~> 3.1)
     net-http (0.6.0)
       uri
-    net-imap (0.4.17)
+    net-imap (0.4.19)
       date
       net-protocol
     net-pop (0.1.2)
@@ -658,7 +658,7 @@ GEM
     thread_safe (0.3.6)
     tilt (2.4.0)
     timecop (0.9.10)
-    timeout (0.4.2)
+    timeout (0.4.3)
     trollop (1.16.2)
     tzinfo (2.0.6)
       concurrent-ruby (~> 1.0)