Update Gemfile with latest compatible dependencies

Author: jedisct1

www/Gemfile

@@ -7,7 +7,7 @@ gem "github-pages", group: :jekyll_plugins
 # Windows and JRuby does not include zoneinfo files, so bundle the tzinfo-data gem
 # and associated library.
 platforms :mingw, :x64_mingw, :mswin, :jruby do
-  gem "tzinfo", "~> 1.2"
+  gem "tzinfo", "~> 2.0"
   gem "tzinfo-data"
 end
 
@@ -19,4 +19,7 @@ gem "wdm", "~> 0.1.1", :platforms => [:mingw, :x64_mingw, :mswin]
 gem "http_parser.rb", "~> 0.6.0", :platforms => [:jruby]
 
 # Needed for Ruby 3.0+
-gem "webrick", "~> 1.7"
+gem "webrick", "~> 1.8"
+
+# Explicitly specify ffi version to avoid compatibility issues
+gem "ffi", "~> 1.15.5"