Add field for group when creating a StagingWorkflow

At creationg time the managers group is mandatory, now we pass it from
the UI

src/api/app/controllers/webui/staging/workflows_controller.rb

@@ -20,6 +20,8 @@ def create
     staging_workflow = @project.build_staging
     authorize staging_workflow
 
+    staging_workflow.managers_group = Group.find_by(title: params[:managers_title])
+
     if staging_workflow.save
       flash[:success] = "Staging Workflow for #{@project.name} was successfully created"
       redirect_to staging_workflow_path(staging_workflow)

src/api/app/views/webui2/webui/staging/workflows/new.html.haml

@@ -7,20 +7,20 @@
     .mb-3
       Adding the staging capability to this project will enable you to group
       requests into staging projects and being able to see how they build together.
-    .text-center
+    .mb-3.w-50.m-auto
       = form_for @staging_workflow, method: :post do |f|
         = hidden_field_tag :project_name, @project
         .form-group#assign-managers-group-modal-input
-          = label_tag(:managers_id, "Managers:")
+          = label_tag(:managers_title, 'Managers:')
           .input-group
             .input-group-prepend
               %span.input-group-text#assign-managers-group-search-icon
                 %i.fa.fa-search
                 %i.fas.fa-spinner.fa-spin.d-none
-            = text_field_tag 'managers_id', '', required: true, placeholder: 'Type to autocomplete...', class: 'form-control', 
-                               data: { autocomplete_groups_url: url_for(controller: '/webui/groups', action: 'autocomplete')}
-
-        = f.submit 'Create Staging Projects', class: 'btn btn-primary'
+            = text_field_tag 'managers_title', '', required: true, placeholder: 'Type to autocomplete...', class: 'form-control',
+                              data: { autocomplete_groups_url: url_for(controller: '/webui/groups', action: 'autocomplete') }
+        .text-center
+          = f.submit 'Create Staging Projects', class: 'btn btn-primary'
 
 - content_for :ready_function do
-  autocompleteStagingManagersGroup();
+  autocompleteStagingManagersGroup();