Upgrade to Decidim 0.27

Gemfile

@@ -4,7 +4,7 @@ source "https://rubygems.org"
 
 ruby RUBY_VERSION
 
-DECIDIM_VERSION = { git: "https://github.com/decidim/decidim", branch: "release/0.26-stable" }.freeze
+DECIDIM_VERSION = { git: "https://github.com/decidim/decidim", branch: "release/0.27-stable" }.freeze
 
 gem "decidim", DECIDIM_VERSION
 gem "decidim-challenges", path: "."
@@ -16,6 +16,9 @@ gem "uglifier", "~> 4.1"
 # More exactly in comments in the homepage and in processes cards in the processes listing
 gem "nokogiri", "1.13.3"
 
+# temporal solution while gems embrace new psych 4 (the default in Ruby 3.1) behavior.
+gem "psych", "< 4"
+
 group :development, :test do
   gem "byebug", ">= 11.1.3"
   gem "decidim-dev", DECIDIM_VERSION
@@ -28,7 +31,7 @@ group :development do
   gem "faker"
   gem "letter_opener_web", "~> 1.3"
   gem "listen", "~> 3.1"
-  gem "spring", "~> 2.0"
-  gem "spring-watcher-listen", "~> 2.0"
+  gem "spring"
+  gem "spring-watcher-listen"
   gem "web-console", "~> 3.5"
 end