Improve bundled gems warnings for subfeatures

Before, when requiring "bigdecimal/math" in a Bundler context:

> /Users/deivid/.asdf/installs/ruby/3.3.0-dev/lib/ruby/3.3.0+0/bigdecimal/math.rb:2: warning: bigdecimal was loaded from the standard library, but will no longer be part of the default gems since Ruby 3.4.0. Add bigdecimal to your Gemfile or gemspec.

After:

> foo.rb:1: warning: bigdecimal/math is found in bigdecimal, which will no longer be part of the default gems since Ruby 3.4.0. Add bigdecimal to your Gemfile or gemspec.

lib/bundled_gems.rb

@@ -89,10 +89,10 @@ def self.find_gem(path)
   end
 
   def self.warning?(name, specs: nil)
-    name = File.path(name) # name can be a feature name or a file path with String or Pathname
-    return if specs.to_a.map(&:name).include?(name.sub(LIBEXT, ""))
-    name = name.tr("/", "-")
-    _t, path = $:.resolve_feature_path(name)
+    feature = File.path(name) # name can be a feature name or a file path with String or Pathname
+    return if specs.to_a.map(&:name).include?(feature.sub(LIBEXT, ""))
+    _t, path = $:.resolve_feature_path(feature)
+    name = feature.tr("/", "-")
     if gem = find_gem(path)
       caller = caller_locations(3, 3).find {|c| c&.absolute_path}
       return if find_gem(caller&.absolute_path)
@@ -106,11 +106,11 @@ def self.warning?(name, specs: nil)
     WARNED[name] = true
     if gem == true
       gem = name
-      "#{name} was loaded from the standard library, but"
+      "#{feature} was loaded from the standard library, but"
     elsif gem
       return if WARNED[gem]
       WARNED[gem] = true
-      "#{name} is found in #{gem}, which"
+      "#{feature} is found in #{gem}, which"
     else
       return
     end + build_message(gem)