[rubygems/rubygems] Refactor replacement of locked path sources

Instead of doing an explicit pass to preserve the source from the
Gemfile when it's a `Source::Gemspec`, add a special case to our generic
source replacement method.

ruby/rubygems@20c8c42380

Author: deivid-rodriguez

lib/bundler/definition.rb

@@ -911,9 +911,6 @@ def converge_path_source_to_gemspec_source(source)
     end
 
     def converge_path_sources_to_gemspec_sources
-      @locked_sources.map! do |source|
-        converge_path_source_to_gemspec_source(source)
-      end
       @locked_specs.each do |spec|
         spec.source &&= converge_path_source_to_gemspec_source(spec.source)
       end

lib/bundler/source_list.rb

@@ -183,6 +183,8 @@ def map_sources(replacement_sources)
       end
 
       path = @path_sources.map do |source|
+        next source if source.is_a?(Source::Gemspec)
+
         replace_source(replacement_sources, source)
       end