Update gemspec's list of packaged files

- drop Rakefile
- add LICENSE.txt and LICENSE-DEPENDENCIES
- omit "app/" from the glob

Author: flavorjones

tailwindcss-ruby.gemspec

@@ -18,7 +18,7 @@ Gem::Specification.new do |spec|
   spec.metadata["changelog_uri"] = "https://github.com/flavorjones/tailwindcss-ruby/blob/main/CHANGELOG.md"
   spec.metadata["rubygems_mfa_required"] = "true"
 
-  spec.files = Dir["{app,lib}/**/*", "MIT-LICENSE", "Rakefile", "README.md"]
+  spec.files = Dir["lib/**/*", "LICENSE.txt", "LICENSE-DEPENDENCIES", "README.md"]
   spec.bindir = "exe"
   spec.executables << "tailwindcss"
   spec.require_paths = ["lib"]