[rubygems/rubygems] Fix lockfile platforms inconveniently added on JRuby

When working with our repository on JRuby locally, I get the following
changes when running `bin/rake setup` in all of our lockfiles

```diff
diff --git a/tool/bundler/dev_gems.rb.lock b/tool/bundler/dev_gems.rb.lock
index https://github.com/rubygems/rubygems/commit/362bf25690d..https://github.com/rubygems/rubygems/commit/74550b2a408 100644
--- a/tool/bundler/dev_gems.rb.lock
+++ b/tool/bundler/dev_gems.rb.lock
@@ -66,6 +66,7 @@ PLATFORMS
   java
   ruby
   universal-java
+  universal-java-22
   x64-mingw-ucrt
   x86-linux
   x86_64-darwin
```

This is inconvenient, so I applied the same strategy we already use on
non JRuby implementations to not add the current platform to the
lockfile if a less specific platform is already there.

ruby/rubygems@812b9cd1e8

Author: deivid-rodriguez

lib/bundler/definition.rb

@@ -490,7 +490,7 @@ def validate_ruby!
     end
 
     def validate_platforms!
-      return if current_platform_locked?
+      return if current_platform_locked? || @platforms.include?(Gem::Platform::RUBY)
 
       raise ProductionError, "Your bundle only supports platforms #{@platforms.map(&:to_s)} " \
         "but your local platform is #{local_platform}. " \
@@ -731,17 +731,17 @@ def reresolve_without(incomplete_specs)
     end
 
     def start_resolution
-      local_platform_needed_for_resolvability = @most_specific_non_local_locked_ruby_platform && !@platforms.include?(local_platform)
+      local_platform_needed_for_resolvability = @most_specific_non_local_locked_platform && !@platforms.include?(local_platform)
       @platforms << local_platform if local_platform_needed_for_resolvability
       add_platform(Gem::Platform::RUBY) if RUBY_ENGINE == "truffleruby"
 
       result = SpecSet.new(resolver.start)
 
       @resolved_bundler_version = result.find {|spec| spec.name == "bundler" }&.version
 
-      if @most_specific_non_local_locked_ruby_platform
-        if spec_set_incomplete_for_platform?(result, @most_specific_non_local_locked_ruby_platform)
-          @platforms.delete(@most_specific_non_local_locked_ruby_platform)
+      if @most_specific_non_local_locked_platform
+        if spec_set_incomplete_for_platform?(result, @most_specific_non_local_locked_platform)
+          @platforms.delete(@most_specific_non_local_locked_platform)
         elsif local_platform_needed_for_resolvability
           @platforms.delete(local_platform)
         end
@@ -758,23 +758,23 @@ def precompute_source_requirements_for_indirect_dependencies?
 
     def current_platform_locked?
       @platforms.any? do |bundle_platform|
-        MatchPlatform.platforms_match?(bundle_platform, local_platform)
+        generic_local_platform == bundle_platform || local_platform === bundle_platform
       end
     end
 
     def add_current_platform
       return if @platforms.include?(local_platform)
 
-      @most_specific_non_local_locked_ruby_platform = find_most_specific_locked_ruby_platform
-      return if @most_specific_non_local_locked_ruby_platform
+      @most_specific_non_local_locked_platform = find_most_specific_locked_platform
+      return if @most_specific_non_local_locked_platform
 
       @new_platforms << local_platform
       @platforms << local_platform
       true
     end
 
-    def find_most_specific_locked_ruby_platform
-      return unless generic_local_platform_is_ruby? && current_platform_locked?
+    def find_most_specific_locked_platform
+      return unless current_platform_locked?
 
       @most_specific_locked_platform
     end