fix: ship the license text in the built gem (#258)

spec.files globbed for "LICENSE" while the file was named LICENSE.txt.
Dir[] answers a pattern it cannot match with an empty list and no
complaint, so every published version through 8.0.0 shipped README.md
and lib/ with no license file at all, which Apache-2.0 requires be
distributed with the work.

Rename LICENSE.txt to LICENSE, matching the other test-kitchen plugins,
and name the file list explicitly rather than globbing it.

Also add the gem metadata RubyGems shows on the gem page and set
rubygems_mfa_required.

Signed-off-by: Tim Smith <tim@mondoo.com>

Author: tas50

LICENSE.txt LICENSELICENSE.txt renamed to LICENSE

@@ -14,9 +14,23 @@ Gem::Specification.new do |spec|
   spec.homepage      = "https://github.com/test-kitchen/kitchen-openstack"
   spec.license       = "Apache-2.0"
 
-  spec.files         = Dir["LICENSE", "README.md", "lib/**/*"]
+  # Named explicitly rather than globbed: Dir[] drops a name it cannot match
+  # without complaining, which is how every published gem up to 8.0.0 came to
+  # ship no license file at all -- the glob asked for "LICENSE" while the file
+  # was named LICENSE.txt. The file is now LICENSE, matching the rest of the
+  # test-kitchen plugins.
+  spec.files         = %w{LICENSE README.md} + Dir["lib/**/*.rb"]
   spec.require_paths = ["lib"]
 
+  spec.metadata = {
+    "bug_tracker_uri" => "#{spec.homepage}/issues",
+    "changelog_uri" => "#{spec.homepage}/blob/main/CHANGELOG.md",
+    "documentation_uri" => "https://kitchen.ci/docs/drivers/openstack/",
+    "homepage_uri" => spec.homepage,
+    "source_code_uri" => spec.homepage,
+    "rubygems_mfa_required" => "true",
+  }
+
   spec.required_ruby_version = ">= 3.1"
 
   spec.add_dependency "test-kitchen", ">= 3.0", "< 5"