Bump minor because we're supporting rails 8.0 and loosening dependencies

Technically, the API is unchanged and this could be a patch release but I prefer
to avoid doing dependency changes of this significance in a pach release.

default_value_for.gemspec

@@ -1,6 +1,6 @@
 Gem::Specification.new do |s|
   s.name                  = %q{default_value_for}
-  s.version               = "4.0.0"
+  s.version               = "4.1.0"
   s.summary               = %q{Provides a way to specify default values for ActiveRecord models}
   s.description           = %q{The default_value_for plugin allows one to define default values for ActiveRecord models in a declarative manner}
   s.email                 = %q{software-signing@phusion.nl}