few more modifications based on comments

lib/gitlab/import_export.rb

@@ -20,6 +20,10 @@ module Gitlab
       "project.bundle"
     end
 
+    def config_file
+      'lib/gitlab/import_export/import_export.yml'
+    end
+
     def version_filename
       'VERSION'
     end

lib/gitlab/import_export/import_export_reader.rb

@@ -2,17 +2,18 @@ module Gitlab
   module ImportExport
     class ImportExportReader
 
-      def initialize(config: 'lib/gitlab/import_export/import_export.yml', shared:)
+      def initialize(shared:)
+        config = ImportExport.config_file
         @shared = shared
         config_hash = YAML.load_file(config).deep_symbolize_keys
         @tree = config_hash[:project_tree]
-        @attributes_parser = Gitlab::ImportExport::AttributesFinder.new(included_attributes: config_hash[:included_attributes],
+        @attributes_finder = Gitlab::ImportExport::AttributesFinder.new(included_attributes: config_hash[:included_attributes],
                                                                         excluded_attributes: config_hash[:excluded_attributes],
                                                                         methods: config_hash[:methods])
       end
 
       def project_tree
-        @attributes_parser.find_included(:project).merge(include: build_hash(@tree))
+        @attributes_finder.find_included(:project).merge(include: build_hash(@tree))
       rescue => e
         @shared.error(e.message)
         false
@@ -25,7 +26,7 @@ module Gitlab
           if model_objects.is_a?(Hash)
             build_json_config_hash(model_objects)
           else
-            @attributes_parser.find(model_objects)
+            @attributes_finder.find(model_objects)
           end
         end
       end
@@ -36,7 +37,7 @@ module Gitlab
         model_object_hash.values.flatten.each do |model_object|
           current_key = model_object_hash.keys.first
 
-          @attributes_parser.parse(current_key) { |hash| @json_config_hash[current_key] ||= hash }
+          @attributes_finder.parse(current_key) { |hash| @json_config_hash[current_key] ||= hash }
 
           handle_model_object(current_key, model_object)
           process_sub_model(current_key, model_object) if model_object.is_a?(Hash)
@@ -66,14 +67,14 @@ module Gitlab
       def create_model_value(current_key, value)
         parsed_hash = { include: value }
 
-        @attributes_parser.parse(value) do |hash|
+        @attributes_finder.parse(value) do |hash|
           parsed_hash = { include: hash_or_merge(value, hash) }
         end
         @json_config_hash[current_key] = parsed_hash
       end
 
       def add_model_value(current_key, value)
-        @attributes_parser.parse(value) { |hash| value = { value => hash } }
+        @attributes_finder.parse(value) { |hash| value = { value => hash } }
         old_values = @json_config_hash[current_key][:include]
         @json_config_hash[current_key][:include] = ([old_values] + [value]).compact.flatten
       end