Avoid ostruct usage

...in order to avoid Ruby warnings in Ruby 3.5.0 about ostruct not being a built-in library.

lib/foreman/export/base.rb

@@ -1,5 +1,4 @@
 require "foreman/export"
-require "ostruct"
 require "pathname"
 require "shellwords"
 
@@ -13,6 +12,9 @@ class Foreman::Export::Base
   # deprecated
   attr_reader :port
 
+  # deprecated
+  ProcessStruct = Struct.new(:name, :process)
+
   def initialize(location, engine, options={})
     @location  = location
     @engine    = engine
@@ -35,10 +37,7 @@ def template
     def @engine.procfile
       Foreman::Export::Base.warn_deprecation!
       @processes.map do |process|
-        OpenStruct.new(
-          :name => @names[process],
-          :process => process
-        )
+        ProcessStruct.new(@names[process], process)
       end
     end
   end