Update ruby to v3.4.2

This MR contains the following updates:

Package	Type	Update	Change
registry.docker.com/library/ruby (source)		patch	3.4.1 -> 3.4.2
registry.docker.com/library/ruby (source)	final	patch	3.4.1-slim -> 3.4.2-slim
ruby (source)		patch	3.4.1 -> 3.4.2

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Configuration

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This MR has been generated by Renovate Bot.

Dockerfile

@@ -3,7 +3,7 @@
 # Make sure RUBY_VERSION matches the Ruby version in .ruby-version and Gemfile
 # renovate: datasource=docker depName=registry.docker.com/library/ruby
 ARG RUBY_VERSION=3.4.2
-FROM registry.docker.com/library/ruby:$RUBY_VERSION-slim AS base
+FROM registry.docker.com/library/ruby:$RUBY_VERSION AS base
 
 # Rails app lives here
 WORKDIR /rails