Revert "Fix to ensure org auditors can see team credentials"

This reverts commit 5dcb0e57d80a3bb0553ca8194890a938257a6e93.

New clarification on what the actual desired behavior of this whole
system means this commit is trash, fixing in a much better way.

awx/main/models/credential.py

@@ -87,11 +87,6 @@ class Credential(PasswordFieldsModel, CommonModelNameNotUnique, ResourceMixin):
         on_delete=models.CASCADE,
         related_name='credentials',
     )
-    teams = models.ManyToManyField(
-        'Team',
-        blank=True,
-        related_name='credentials',
-    )
     kind = models.CharField(
         max_length=32,
         choices=KIND_CHOICES,
@@ -231,7 +226,6 @@ class Credential(PasswordFieldsModel, CommonModelNameNotUnique, ResourceMixin):
     read_role = ImplicitRoleField(parent_role=[
         'singleton:' + ROLE_SINGLETON_SYSTEM_AUDITOR,
         'organization.auditor_role',
-        'teams.auditor_role',
         'use_role',
         'admin_role',
     ])