deps: Use concurrent-ruby v1.3.4 (#2533)

Author: toshimaru

.github/dependabot.yml

@@ -22,6 +22,8 @@ updates:
       # nokogiri v1.18.0+ requires Ruby 3.0+
       - dependency-name: "nokogiri"
         versions: [">= 1.18.0"]
+      - dependency-name: "concurrent-ruby"
+        versions: [">= 1.3.5"]
     groups:
       debug-gem:
         patterns: