Define a `get_absolute_url()` method on NetBoxModel

[jeremystretch]

Proposed Changes

Add a get_absolute_url() method on NetBoxModel to dynamically return the appropriate URL based on the model's app_label and model_name Meta attributes:

    def get_absolute_url(self):
        return reverse(f'{self._meta.app_label}:{model_name}', args=[self.pk])

Justification

The vast majority of models in NetBox declare this method explicitly. Moving it to NetBoxModel allows us to remove boilerplate code while still permitting customization on individual models.

[sleepinggenius2]

Would the proposed solution work for plugin models that inherit from NetBoxModel too? It would be nice to do away with the boilerplate there as well.

[jeremystretch]

A get_absolute_url() method has been added to the NetBoxFeatureSet mixin, which is used by NetBoxModel, OrganizationalModel, and NestedGroupModel.