[WIP] DO NOT MERGE: SQL constraint problem showcase

* Add new module that depends on purchase so that it's installed and the SQL constraint is added
* Due to the module name, the module is going to be loaded later
* On date_range tests, without post_install, tests are failing on the company creation

date_range/tests/test_date_range.py

@@ -8,8 +8,6 @@ from odoo.tests.common import TransactionCase
 
 
 class DateRangeTest(TransactionCase):
-    post_install = True
-    at_install = False
 
     def setUp(self):
         super(DateRangeTest, self).setUp()

date_range/tests/test_date_range_generator.py

@@ -10,8 +10,6 @@ from odoo.tests.common import TransactionCase
 
 
 class DateRangeGeneratorTest(TransactionCase):
-    post_install = True
-    at_install = False
 
     def setUp(self):
         super(DateRangeGeneratorTest, self).setUp()

date_range/tests/test_date_range_type.py

@@ -9,8 +9,6 @@ from odoo.tools import mute_logger
 
 
 class DateRangeTypeTest(TransactionCase):
-    post_install = True
-    at_install = False
 
     def setUp(self):
         super(DateRangeTypeTest, self).setUp()

zzz/__manifest__.py

@@ -0,0 +1,14 @@
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).
+{
+    "name": "ZZZ",
+    "version": "12.0.1.0.0",
+    "category": "Uncategorized",
+    "website": "https://github.com/oca/server-ux",
+    "author": "Odoo Community Association (OCA)",
+    "license": "AGPL-3",
+    "installable": True,
+    "depends": [
+        "purchase",
+        "date_range",
+    ],
+}