Install Ruby 3.0.4 because the latest is not working

Related to https://github.com/rbenv/ruby-build/discussions/1961

templates/base.pkr.hcl

@@ -46,8 +46,8 @@ build {
       "brew install rbenv",
       "echo 'if which rbenv > /dev/null; then eval \"$(rbenv init -)\"; fi' >> ~/.zprofile",
       "source ~/.zprofile",
-      "rbenv install $(rbenv install -l | grep -v - | tail -1)",
-      "rbenv global $(rbenv install -l | grep -v - | tail -1)",
+      "rbenv install 3.0.4",
+      "rbenv global 3.0.4",
       "sudo gem install bundler",
     ]
   }