api: fix generic api path functions

Library/Homebrew/api/analytics.rb

@@ -7,10 +7,9 @@ module Homebrew
     #
     # @api private
     module Analytics
+      class << self
         extend T::Sig
 
-      module_function
-
         sig { returns(String) }
         def analytics_api_path
           "analytics"
@@ -24,5 +23,6 @@ module Homebrew
       end
     end
   end
+end
 
 require "extend/os/api/analytics"

Library/Homebrew/api/bottle.rb

@@ -9,10 +9,9 @@ module Homebrew
     #
     # @api private
     module Bottle
+      class << self
         extend T::Sig
 
-      module_function
-
         sig { returns(String) }
         def bottle_api_path
           "bottle"
@@ -91,5 +90,6 @@ module Homebrew
       end
     end
   end
+end
 
 require "extend/os/api/bottle"

Library/Homebrew/api/cask.rb

@@ -7,10 +7,9 @@ module Homebrew
     #
     # @api private
     module Cask
+      class << self
         extend T::Sig
 
-      module_function
-
         sig { params(name: String).returns(Hash) }
         def fetch(name)
           Homebrew::API.fetch "cask/#{name}.json"
@@ -18,3 +17,4 @@ module Homebrew
       end
     end
   end
+end

Library/Homebrew/api/formula.rb

@@ -7,10 +7,9 @@ module Homebrew
     #
     # @api private
     module Formula
+      class << self
         extend T::Sig
 
-      module_function
-
         sig { returns(String) }
         def formula_api_path
           "formula"
@@ -24,5 +23,6 @@ module Homebrew
       end
     end
   end
+end
 
 require "extend/os/api/formula"

Library/Homebrew/api/versions.rb

@@ -7,10 +7,9 @@ module Homebrew
     #
     # @api private
     module Versions
+      class << self
         extend T::Sig
 
-      module_function
-
         def formulae
           # The result is cached by Homebrew::API.fetch
           Homebrew::API.fetch "versions-formulae.json"
@@ -50,3 +49,4 @@ module Homebrew
       end
     end
   end
+end