extend/os: clean up requires

These need to be after the original module/class definitions
for the monkey-patching to work correctly.

Library/Homebrew/cmd/update-report.rb

@@ -9,7 +9,6 @@ require "description_cache_store"
 require "cli/parser"
 require "settings"
 require "linuxbrew-core-migration"
-require "extend/os/cmd/update-report"
 
 module Homebrew
   extend T::Sig
@@ -305,6 +304,8 @@ module Homebrew
   end
 end
 
+require "extend/os/cmd/update-report"
+
 class Reporter
   class ReporterRevisionUnsetError < RuntimeError
     def initialize(var_name)

Library/Homebrew/dev-cmd/update-test.rb

@@ -2,8 +2,6 @@
 # frozen_string_literal: true
 
 require "cli/parser"
-require "extend/os/dev-cmd/update-test"
-
 module Homebrew
   extend T::Sig
 
@@ -151,6 +149,6 @@ module Homebrew
     end
     tags
   end
-
-  alias generic_git_tags git_tags
 end
+
+require "extend/os/dev-cmd/update-test"

Library/Homebrew/extend/os/linux/dev-cmd/update-test.rb

@@ -6,6 +6,10 @@ module Homebrew
 
   module_function
 
+  class << self
+    alias generic_git_tags git_tags
+  end
+
   def git_tags
     tags = generic_git_tags
     tags = Utils.popen_read("git tag --list | sort -rV") if tags.blank?