Bump net-imap from 0.2.2 to 0.2.3

Bumps [net-imap](https://github.com/ruby/net-imap) from 0.2.2 to 0.2.3.
- [Release notes](https://github.com/ruby/net-imap/releases)
- [Commits](https://github.com/ruby/net-imap/compare/v0.2.2...v0.2.3)

---
updated-dependencies:
- dependency-name: net-imap
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Gemfile.lock

@@ -153,7 +153,7 @@ GEM
     mini_portile2 (2.6.1)
     minitest (5.15.0)
     msgpack (1.4.2)
-    net-imap (0.2.2)
+    net-imap (0.2.3)
       digest
       net-protocol
       strscan