fix(tasks): get all tasks from parent projects

pkg/db/fixtures/projects.yml

@@ -104,6 +104,7 @@
   identifier: test12
   owner_id: 6
   position: 12
+  parent_project_id: 27
   updated: 2018-12-02 15:13:12
   created: 2018-12-01 15:13:12
 -
@@ -131,6 +132,7 @@
   identifier: test15
   owner_id: 6
   position: 15
+  parent_project_id: 28
   updated: 2018-12-02 15:13:12
   created: 2018-12-01 15:13:12
 -
@@ -188,6 +190,7 @@
   identifier: test21
   owner_id: 1
   position: 21
+  parent_project_id: 22
   updated: 2018-12-02 15:13:12
   created: 2018-12-01 15:13:12
 -
@@ -253,3 +256,15 @@
   parent_project_id: 25
   updated: 2018-12-02 15:13:12
   created: 2018-12-01 15:13:12
+-
+  id: 27
+  title: Test27
+  owner_id: 6
+  updated: 2018-12-02 15:13:12
+  created: 2018-12-01 15:13:12
+-
+  id: 28
+  title: Test28
+  owner_id: 6
+  updated: 2018-12-02 15:13:12
+  created: 2018-12-01 15:13:12