Update bundled gems list at 2022-10-04

NEWS.md

@@ -218,6 +218,7 @@ Note: We're only listing outstanding class updates.
     * timeout 0.3.0
 *   The following bundled gems are updated.
     * minitest 5.16.3
+    * test-unit 3.5.5
     * net-imap 0.3.1
     * net-pop 0.1.2
     * net-smtp 0.3.2

gems/bundled_gems

@@ -2,7 +2,7 @@
 minitest        5.16.3  https://github.com/seattlerb/minitest
 power_assert    2.0.1   https://github.com/ruby/power_assert
 rake            13.0.6  https://github.com/ruby/rake
-test-unit       3.5.3   https://github.com/test-unit/test-unit
+test-unit       3.5.5   https://github.com/test-unit/test-unit
 rexml           3.2.5   https://github.com/ruby/rexml
 rss             0.2.9   https://github.com/ruby/rss
 net-ftp         0.1.3   https://github.com/ruby/net-ftp