Add id to jira project field

This adds a missing id to the jira project field, allowing it to be
filled in the test and the tests to pass

app/assets/javascripts/integrations/edit/components/jira_issues_fields.vue

@@ -119,10 +119,12 @@ export default {
     <template v-if="showJiraIssuesIntegration">
       <gl-form-group
         :label="s__('JiraService|Jira project key')"
+        label-for="service_project_key"
         :invalid-feedback="__('This field is required.')"
         :state="validProjectKey"
       >
         <gl-form-input
+          id="service_project_key"
           v-model="projectKey"
           name="service[project_key]"
           :placeholder="s__('JiraService|e.g. AB')"

ee/spec/features/projects/services/user_activates_jira_spec.rb

@@ -16,6 +16,7 @@ RSpec.describe 'User activates Jira', :js do
 
         visit_project_integration('Jira')
         fill_form
+        fill_in 'service_project_key', with: 'AB'
         click_test_integration
       end