Move render_specific_not_found to SharedHelpers

Issues:
* https://progress.opensuse.org/issues/163931
* https://progress.opensuse.org/issues/163592
* https://progress.opensuse.org/issues/163757

Prevents:

    Can't locate object method "render_specific_not_found" via package "OpenQA::Shared::Controller::Running"

lib/OpenQA/Shared/Plugin/SharedHelpers.pm

@@ -20,6 +20,7 @@ sub register ($self, $app, @) {
     $app->helper(is_operator => \&_is_operator);
     $app->helper(is_admin => \&_is_admin);
     $app->helper(is_local_request => \&_is_local_request);
+    $app->helper(render_specific_not_found => \&_render_specific_not_found);
 }
 
 # returns the isotovideo command server web socket URL and the VNC argument for the given job or undef if not available
@@ -73,4 +74,17 @@ sub _is_local_request ($c) {
     return $address eq '127.0.0.1' || $address eq '::1';
 }
 
+sub _render_specific_not_found ($c) {
+    my ($c, $title, $error_message) = @_;
+
+    $c->stash(
+        title => $title,
+        error_message => $error_message,
+    );
+    return $c->render(
+        template => 'main/specific_not_found',
+        status => 404,
+    );
+}
+
 1;

lib/OpenQA/WebAPI/Plugin/Helpers.pm

@@ -286,20 +286,6 @@ sub register ($self, $app, $config) {
                 });
         });
 
-    $app->helper(
-        render_specific_not_found => sub {
-            my ($c, $title, $error_message) = @_;
-
-            $c->stash(
-                title => $title,
-                error_message => $error_message,
-            );
-            return $c->render(
-                template => 'main/specific_not_found',
-                status => 404,
-            );
-        });
-
     $app->helper(
         populate_hash_with_needle_timestamps_and_urls => sub {
             my ($c, $needle, $hash) = @_;