Update scheduled variable translation strings

See
https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/12372#note_34142476

app/views/projects/pipeline_schedules/_form.html.haml

@@ -25,7 +25,7 @@
   .form-group
     .col-md-9
       %label.label-light
-        #{ _('Variables') }
+        #{ s_('PipelineSchedules|Variables') }
       %ul.js-pipeline-variable-list.pipeline-variable-list
         - @schedule.variables.each do |variable|
           = render 'variable_row', id: variable.id, key: variable.key, value: variable.value

app/views/projects/pipeline_schedules/_variable_row.html.haml

@@ -7,10 +7,10 @@
   %input.js-user-input.pipeline-variable-key-input.form-control{ type: "text",
     name: "schedule[variables_attributes][][key]",
     value: key,
-    placeholder: _('Input variable key') }
+    placeholder: s_('PipelineSchedules|Input variable key') }
   %textarea.js-user-input.pipeline-variable-value-input.form-control{ rows: 1,
     name: "schedule[variables_attributes][][value]",
-    placeholder: _('Input variable value') }
+    placeholder: s_('PipelineSchedules|Input variable value') }
     = value
-  %button.js-row-remove-button.pipeline-variable-row-remove-button{ 'aria-label': _('Remove variable row') }
+  %button.js-row-remove-button.pipeline-variable-row-remove-button{ 'aria-label': s_('PipelineSchedules|Remove variable row') }
     %i.fa.fa-minus-circle{ 'aria-hidden': "true" }

locale/en/gitlab.po

@@ -619,6 +619,12 @@ msgstr ""
 msgid "PipelineSchedules|Inactive"
 msgstr ""
 
+msgid "PipelineSchedules|Input variable key"
+msgstr ""
+
+msgid "PipelineSchedules|Input variable value"
+msgstr ""
+
 msgid "PipelineSchedules|Next Run"
 msgstr ""
 
@@ -628,12 +634,18 @@ msgstr ""
 msgid "PipelineSchedules|Provide a short description for this pipeline"
 msgstr ""
 
+msgid "PipelineSchedules|Remove variable row"
+msgstr ""
+
 msgid "PipelineSchedules|Take ownership"
 msgstr ""
 
 msgid "PipelineSchedules|Target"
 msgstr ""
 
+msgid "PipelineSchedules|Variables"
+msgstr ""
+
 msgid "PipelineSheduleIntervalPattern|Custom"
 msgstr ""