Use ugly `zypper lr --uri` hack to get around failure if the `base_url`
already exists under a different name:
```
ID: salt-pkgrepo-install-saltstack-suse
Function: pkgrepo.managed
Name: systemsmanagement_saltstack_products
Result: False
Comment: Failed to configure repo 'systemsmanagement_saltstack_products':
Repository 'systemsmanagement_saltstack_products' already exists as 'systemsmanagement_saltstack'.
Started: 09:28:39.154054
Duration: 2760.727 ms
```
Upstream code:
* 45cc49daed/salt/modules/zypperpkg.py (L1262-L1265)
d5320a35ed