[rubygems/rubygems] Use splatted args to `lockfile_platforms_for`

Nicer :)

https://github.com/rubygems/rubygems/commit/c0ab2893c3

spec/bundler/bundler/definition_spec.rb

@@ -154,7 +154,7 @@ RSpec.describe Bundler::Definition do
             only_java (1.1-java)
 
         PLATFORMS
-          #{lockfile_platforms_for(["java", specific_local_platform])}
+          #{lockfile_platforms_for("java", specific_local_platform)}
 
         DEPENDENCIES
           only_java

spec/bundler/install/gemfile/gemspec_spec.rb

@@ -674,7 +674,7 @@ RSpec.describe "bundle install from an existing gemspec" do
             railties (6.1.4)
 
         PLATFORMS
-          #{lockfile_platforms_for(["java", specific_local_platform])}
+          #{lockfile_platforms_for("java", specific_local_platform)}
 
         DEPENDENCIES
           activeadmin!

spec/bundler/lock/lockfile_spec.rb

@@ -982,7 +982,7 @@ RSpec.describe "the lockfile format" do
           rack (1.0.0)
 
       PLATFORMS
-        #{lockfile_platforms_for(["java", specific_local_platform])}
+        #{lockfile_platforms_for("java", specific_local_platform)}
 
       DEPENDENCIES
         rack

spec/bundler/runtime/platform_spec.rb

@@ -86,7 +86,7 @@ RSpec.describe "Bundler.setup with multi platform stuff" do
           racc (1.5.2)
 
       PLATFORMS
-        #{lockfile_platforms_for(["ruby", specific_local_platform])}
+        #{lockfile_platforms_for("ruby", specific_local_platform)}
 
       DEPENDENCIES
         nokogiri (~> 1.11)

spec/bundler/support/platforms.rb

@@ -104,10 +104,10 @@ module Spec
     end
 
     def lockfile_platforms
-      lockfile_platforms_for([specific_local_platform])
+      lockfile_platforms_for(specific_local_platform)
     end
 
-    def lockfile_platforms_for(platforms)
+    def lockfile_platforms_for(*platforms)
       platforms.map(&:to_s).sort.join("\n  ")
     end
   end