add delete mapping route, controller and implementation

services/officeRnD/resources.js

@@ -73,6 +73,10 @@ const getMappingsFromDatabase = () => {
     return db.officeResourceMapping.findAll();
 };
 
+const deleteMappingById = (id) => {
+    return db.officeResourceMapping.destroy({where: {id}});
+};
+
 const saveNewMappingToDatabase = (mapping) => {
     return db.officeResourceMapping.findOrCreate({where: {...mapping}, defaults: {...mapping}});
 };
@@ -83,4 +87,5 @@ module.exports = {
     fetchResources,
     getResourceMappings,
     saveNewMappingToDatabase,
+    deleteMappingById,
 };