Include source_code_uri in gemspec, version changelog_uri

See #3684

Co-authored-by: TonyCTHsu <tonyc.t.hsu@gmail.com>

datadog.gemspec

@@ -29,7 +29,8 @@ Gem::Specification.new do |spec|
 
   if spec.respond_to?(:metadata)
     spec.metadata['allowed_push_host'] = 'https://rubygems.org'
-    spec.metadata['changelog_uri'] = 'https://github.com/DataDog/dd-trace-rb/blob/master/CHANGELOG.md'
+    spec.metadata['changelog_uri'] = "https://github.com/DataDog/dd-trace-rb/blob/v#{spec.version}/CHANGELOG.md"
+    spec.metadata['source_code_uri'] = "https://github.com/DataDog/dd-trace-rb/tree/v#{spec.version}"
   else
     raise 'RubyGems 2.0 or newer is required to protect against public gem pushes.'
   end

spec/datadog/release_gem_spec.rb

@@ -107,5 +107,17 @@
         expect(gemspec.licenses).to contain_exactly('BSD-3-Clause', 'Apache-2.0')
       end
     end
+
+    describe '#metadata' do
+      it do
+        {
+          'allowed_push_host' => 'https://rubygems.org',
+          'changelog_uri' => "https://github.com/DataDog/dd-trace-rb/blob/v#{gemspec.version}/CHANGELOG.md",
+          'source_code_uri' => "https://github.com/DataDog/dd-trace-rb/tree/v#{gemspec.version}"
+        }.each do |key, value|
+          expect(gemspec.metadata[key]).to eq(value)
+        end
+      end
+    end
   end
 end