Use named parameters in ERB.new function

Since Ruby v3 the meaning of 2nd and 3rd parameters to ERB.new changed
as well as the way the arguments should be passed.
It requires a named 2nd parameter now.

Also update Dockerfile ruby image version for local testing.

.gitignore

@@ -16,7 +16,7 @@ samples/consul-ui/decorators.js
 /samples/hosts
 /samples/hosts_per_services
 /samples/prometheus_consul_coordinates
-/samples/ready
+/samples/consul-ui/ready
 /samples/render_template_from_kv
 /samples/consul_template
 /samples/metrics

Dockerfile

@@ -1,4 +1,4 @@
-FROM ruby:2.5
+FROM ruby:3.2
 
 WORKDIR /usr/src/app
 COPY . .

lib/consul/async/consul_template.rb

@@ -318,7 +318,7 @@ def render(tpl, tpl_file_path, params = {}, current_template_info: nil)
           params: params,
           template_info: tpl_info
         }
-        result = ERB.new(tpl, nil, @trim_mode).result(binding)
+        result = ERB.new(tpl, trim_mode: @trim_mode).result(binding)
         raise "Result is not a string :='#{result}' for #{tpl_file_path}" unless result.is_a?(String)
 
         @context = old_value