fix(migrations) : foreign key order

Fix dropping FKs before indexes.

Author: qschmick

database/migrations/2018_07_06_165603_add_indexes_for_tasks.php

@@ -45,17 +45,22 @@ public function up()
      */
     public function down()
     {
+        Schema::table(config('totem.table_prefix').'task_results', function (Blueprint $table) {
+            $table->dropForeign('task_results_task_id_fk');
+        });
         Schema::table(config('totem.table_prefix').'task_results', function (Blueprint $table) {
             $table->dropIndex('task_results_task_id_idx');
             $table->dropIndex('task_results_ran_at_idx');
-            $table->dropForeign('task_results_task_id_fk');
         });
 
         Schema::table(config('totem.table_prefix').'task_frequencies', function (Blueprint $table) {
-            $table->dropIndex('task_frequencies_task_id_idx');
             $table->dropForeign('task_frequencies_task_id_fk');
         });
 
+        Schema::table(config('totem.table_prefix').'task_frequencies', function (Blueprint $table) {
+            $table->dropIndex('task_frequencies_task_id_idx');
+        });
+
         Schema::table(config('totem.table_prefix').'tasks', function (Blueprint $table) {
             $table->dropIndex('tasks_is_active_idx');
             $table->dropIndex('tasks_dont_overlap_idx');