Added GetPluginID method and tests (#27281)

A new method, GetPluginID, has been added to the Manifest model. This function returns the ID of a plugin. Corresponding unit tests have also been implemented to ensure that this function works as expected. The test cases cover scenarios where IDs are the same and different.

server/public/model/manifest.go

@@ -322,6 +322,10 @@ func (m *Manifest) IsValid() error {
 	return nil
 }
 
+func (m *Manifest) GetPluginID() string {
+	return m.Id
+}
+
 func (s *PluginSettingsSchema) isValid() error {
 	for _, setting := range s.Settings {
 		err := setting.isValid()