Improve configuration reset in specs

spec/datadog/tracing/contrib/rack/http_route_spec.rb

@@ -8,13 +8,13 @@
 RSpec.describe 'Rack testing for http.route' do
   include Rack::Test::Methods
 
-  before do
+  around do |example|
     Datadog.configure do |c|
       c.tracing.instrument :rack
     end
-  end
 
-  after do
+    example.run
+  ensure
     Datadog.configuration.tracing[:rack].reset!
   end
 

spec/datadog/tracing/contrib/rails/support/rails7.rb

@@ -134,11 +134,11 @@ def initialize(files, dirs = {}, &block)
     end
   end
 
-  before do
+  around do |example|
     reset_rails_configuration!
-  end
 
-  after do
+    example.run
+  ensure
     reset_rails_configuration!
 
     # Push this to base when Rails 3 removed