Bump net-imap from 0.4.14 to 0.4.20

Bumps [net-imap](https://github.com/ruby/net-imap) from 0.4.14 to 0.4.20.
- [Release notes](https://github.com/ruby/net-imap/releases)
- [Commits](ruby/net-imap@v0.4.14...v0.4.20)

---
updated-dependencies:
- dependency-name: net-imap
  dependency-version: 0.4.20
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

Gemfile.lock

@@ -109,7 +109,7 @@ GEM
     concurrent-ruby (1.3.5)
     connection_pool (2.5.4)
     crass (1.0.6)
-    date (3.3.4)
+    date (3.4.1)
     drb (2.2.3)
     ed25519 (1.3.0)
     erubi (1.13.1)
@@ -136,7 +136,7 @@ GEM
     mini_mime (1.1.5)
     mini_portile2 (2.8.9)
     minitest (5.25.5)
-    net-imap (0.4.14)
+    net-imap (0.4.20)
       date
       net-protocol
     net-pop (0.1.2)
@@ -237,7 +237,7 @@ GEM
     stringio (3.1.7)
     thor (1.3.1)
     tilt (2.0.11)
-    timeout (0.4.1)
+    timeout (0.4.3)
     turbolinks (5.2.1)
       turbolinks-source (~> 5.2)
     turbolinks-source (5.2.0)