Update dependencies and add pipelines (#2)

* Update Ruby/Rails/other deps
* Unlock Rails and tie to master
  * Gain access to 7.1 incoming feature allowing CI without secret_key_base
* Use Rails 7.1 Dockerfile
* Pipeline for some merge checks
* Pipeline to deploy

Reviewed-on: #2

Dockerfile

@@ -0,0 +1,27 @@
+# Make sure it matches the Ruby version in .ruby-version and Gemfile
+ARG RUBY_VERSION=3.2.0
+FROM ruby:$RUBY_VERSION
+
+# Set production environment
+ENV RAILS_LOG_TO_STDOUT="1" \
+    RAILS_SERVE_STATIC_FILES="true" \
+    RAILS_ENV="production" \
+    BUNDLE_WITHOUT="development:test"
+
+# Install application gems
+COPY Gemfile Gemfile.lock ./
+RUN bundle install
+
+# Copy application code
+COPY . .
+
+# Precompile bootsnap code for faster boot times
+RUN bundle exec bootsnap precompile --gemfile app/ lib/
+
+# Precompiling assets for production without requiring secret RAILS_MASTER_KEY
+RUN SECRET_KEY_BASE_DUMMY=1 bundle exec rails assets:precompile
+
+# Entrypoint prepares database and starts app on 0.0.0.0:3000 by default,
+# but can also take a rails command, like "console" or "runner" to start instead.
+ENTRYPOINT ["/rails/bin/docker-entrypoint"]
+EXPOSE 3000