try a better version declaration

Gemfile

@@ -1,5 +1,5 @@
 source "https://rubygems.org"
-ruby '3.0.0'
+ruby '>=3.0'
 # Hello! This is where you manage which Jekyll version is used to run.
 # When you want to use a different version, change it below, save the
 # file and run `bundle install`. Run Jekyll with `bundle exec`, like so: