Merge branch 'label-filter-path-fix' into 'master'

Fixed URL on label button when filtering

## What does this MR do?

Gives the filtered labels the correct URL. Previously they tried to link to `labels#show` whereas now it links to the correct filter path.

## What are the relevant issue numbers?

Closes #19005

See merge request !4897
(cherry picked from commit d3d9df5a)

CHANGELOG

@@ -6,6 +6,7 @@ v 8.9.4
   - Fixed search field blur not removing focus. !4704
   - Resolve "Sub nav isn't showing on file view". !4890
   - Fixes middle click and double request when navigating through the file browser. !4891
+  - Fixed URL on label button when filtering. !4897
 
 v 8.9.3
   - Fix encrypted data backwards compatibility after upgrading attr_encrypted gem. !4963

app/helpers/labels_helper.rb

@@ -34,10 +34,7 @@ module LabelsHelper
   # Returns a String
   def link_to_label(label, project: nil, type: :issue, tooltip: true, css_class: nil, &block)
     project ||= @project || label.project
-    link = send("namespace_project_#{type.to_s.pluralize}_path",
-                project.namespace,
-                project,
-                label_name: [label.name])
+    link = label_filter_path(project, label, type: type)
 
     if block_given?
       link_to link, class: css_class, &block
@@ -46,6 +43,13 @@ module LabelsHelper
     end
   end
 
+  def label_filter_path(project, label, type: issue)
+    send("namespace_project_#{type.to_s.pluralize}_path",
+                project.namespace,
+                project,
+                label_name: [label.name])
+  end
+
   def project_label_names
     @project.labels.pluck(:title)
   end

app/views/shared/_labels_row.html.haml

 - labels.each do |label|
   %span.label-row.btn-group{ role: "group", aria: { label: escape_once(label.name) }, style: "color: #{text_color_for_bg(label.color)}" }
-    = link_to namespace_project_label_path(@project.namespace, @project, label),
+    = link_to label_filter_path(@project, label, type: controller.controller_name),
       class: "btn btn-transparent has-tooltip",
       style: "background-color: #{label.color};",
       title: escape_once(label.description),