TF: standardize `test_model_common_attributes` for language models
# What does this PR do?

`test_model_common_attributes` was overridden in most TF LMs because:
1. it was not able to handle legacy classes with LM heads (there was not a single set of autoclasses that would catch them)
2. many modern decoder-only LMs do not have a bias in the LM head

This PR adapts the test to account for these 2 cases, and removes a large number of overridden tests.

_The documentation is not available anymore as the PR was closed or merged._<|||||>@amyeroberts now with deprecation messages (as opposed to deletions) and pytest asserts 🤗 
@Rocketknight1 ping 🙌 