Adds tags on contact assignment (#13328)

* adds tags on contact assignments #12882

* updated migration

* added tags on import form

* adds TagsMixin on ContactAssignmentType #12882

* Misc cleanup

---------

Co-authored-by: Jeremy Stretch <jstretch@netboxlabs.com>

netbox/tenancy/migrations/0011_contactassignment_tags.py

@@ -0,0 +1,20 @@
+# Generated by Django 4.1.10 on 2023-07-08 07:17
+
+from django.db import migrations
+import taggit.managers
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('extras', '0097_customfield_remove_choices'),
+        ('tenancy', '0010_tenant_relax_uniqueness'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='contactassignment',
+            name='tags',
+            field=taggit.managers.TaggableManager(through='extras.TaggedItem', to='extras.Tag'),
+        ),
+    ]