Increase benchmark validation timeout (#4225)

* Increase benchmark validation timeout

* Reduce to 20

spec/datadog/tracing/validate_benchmarks_spec.rb

@@ -16,7 +16,7 @@
   benchmarks_to_validate.each do |benchmark|
     describe benchmark do
       it 'runs without raising errors' do
-        expect_in_fork do
+        expect_in_fork(timeout_seconds: 20) do
           load "./benchmarks/#{benchmark}.rb"
         end
       end