Remove "incoming/" section from the debian upload route

See https://gitlab.com/gitlab-org/gitlab-workhorse/-/issues/343

lib/api/debian_project_packages.rb

@@ -20,10 +20,10 @@ module API
           requires :file_name, type: String, desc: 'The file name'
         end
 
-        namespace 'incoming/:file_name', requirements: FILE_NAME_REQUIREMENTS do
+        namespace ':file_name', requirements: FILE_NAME_REQUIREMENTS do
           content_type :json, Gitlab::Workhorse::INTERNAL_API_CONTENT_TYPE
 
-          # PUT {projects|groups}/:id/packages/debian/incoming/:file_name
+          # PUT {projects|groups}/:id/packages/debian/:file_name
           params do
             requires :file, type: ::API::Validations::Types::WorkhorseFile, desc: 'The package file to be published (generated by Multipart middleware)'
           end
@@ -42,7 +42,7 @@ module API
             forbidden!
           end
 
-          # PUT {projects|groups}/:id/packages/debian/incoming/:file_name/authorize
+          # PUT {projects|groups}/:id/packages/debian/:file_name/authorize
           route_setting :authentication, deploy_token_allowed: true, basic_auth_personal_access_token: true, job_token_allowed: :basic_auth
           put 'authorize' do
             authorize_workhorse!(

spec/requests/api/debian_project_packages_spec.rb

@@ -36,16 +36,16 @@ RSpec.describe API::DebianProjectPackages do
       it_behaves_like 'Debian project repository GET endpoint', :success, 'TODO File'
     end
 
-    describe 'PUT projects/:id/packages/debian/incoming/:file_name' do
+    describe 'PUT projects/:id/packages/debian/:file_name' do
       let(:method) { :put }
-      let(:url) { "/projects/#{project.id}/packages/debian/incoming/#{file_name}" }
+      let(:url) { "/projects/#{project.id}/packages/debian/#{file_name}" }
 
       it_behaves_like 'Debian project repository PUT endpoint', :created, nil
     end
 
-    describe 'PUT projects/:id/packages/debian/incoming/:file_name/authorize' do
+    describe 'PUT projects/:id/packages/debian/:file_name/authorize' do
       let(:method) { :put }
-      let(:url) { "/projects/#{project.id}/packages/debian/incoming/#{file_name}/authorize" }
+      let(:url) { "/projects/#{project.id}/packages/debian/#{file_name}/authorize" }
 
       it_behaves_like 'Debian project repository PUT endpoint', :created, nil, is_authorize: true
     end