fix(tombstone-library): generate Rakefile for release builds

toys/tombstone-library/.data/rakefile-template.erb

@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+# Copyright <%= cur_year %> Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+require "bundler/setup"
+require "bundler/gem_tasks"

toys/tombstone-library/.toys.rb

@@ -97,6 +97,7 @@ def generate_files
     generate_one "LICENSE.md", "license-template.erb"
     generate_one "#{gem_name}.gemspec", "gemspec-template.erb"
     generate_one ".yardopts", "yardopts-template.erb"
+    generate_one "Rakefile", "rakefile-template.erb"
     mkdir_p "lib/#{namespace_dir}"
     generate_one "lib/#{namespace_dir}/version.rb", "version-template.erb"
   end