Fix Mkdocs Formatting Warnings

Here are some warnings produced when [running](https://google.github.io/sbsim/docs-site/#previewing) the mkdocs preview server.

Let's resolve them.

```
WARNING - griffe: smart_control/dataset/dataset.py:71: No type or annotation for parameter 'building'
WARNING - griffe: smart_control/dataset/dataset.py:72: No type or annotation for parameter 'partition'
WARNING - griffe: smart_control/dataset/dataset.py:75: No type or annotation for returned value 1
WARNING - griffe: smart_control/dataset/dataset.py:51: No type or annotation for parameter 'building'
WARNING - griffe: smart_control/dataset/dataset.py:54: No type or annotation for returned value 1

WARNING - griffe: smart_control/models/base_normalizer.py:53: No type or annotation for parameter 'name'

WARNING - griffe: smart_control/reinforcement_learning/agents/sac_agent.py:47: Confusing indentation for continuation line 7 in docstring, should be 4 * 2 = 8 spaces, not 6
WARNING - griffe: smart_control/reinforcement_learning/agents/sac_agent.py:50: Confusing indentation for continuation line 10 in docstring, should be 4 * 2 = 8 spaces, not 6
WARNING - griffe: smart_control/reinforcement_learning/agents/sac_agent.py:52: Confusing indentation for continuation line 12 in docstring, should be 4 * 2 = 8 spaces, not 6
WARNING - griffe: smart_control/reinforcement_learning/agents/sac_agent.py:54: Confusing indentation for continuation line 14 in docstring, should be 4 * 2 = 8 spaces, not 6
WARNING - griffe: smart_control/reinforcement_learning/agents/sac_agent.py:67: Confusing indentation for continuation line 27 in docstring, should be 4 * 2 = 8 spaces, not 6

WARNING - griffe: smart_control/reinforcement_learning/observers/rendering_observer.py:59: Confusing indentation for continuation line 6 in docstring, should be 4 * 2 = 8 spaces, not 6
WARNING - griffe: smart_control/reinforcement_learning/observers/rendering_observer.py:61: Confusing indentation for continuation line 8 in docstring, should be 4 * 2 = 8 spaces, not 6
WARNING - griffe: smart_control/reinforcement_learning/observers/rendering_observer.py:63: Confusing indentation for continuation line 10 in docstring, should be 4 * 2 = 8 spaces, not 6
WARNING - griffe: smart_control/reinforcement_learning/observers/rendering_observer.py:58: No type or annotation for parameter 'env'

WARNING - griffe: smart_control/reinforcement_learning/replay_buffer/replay_buffer.py:162: Confusing indentation for continuation line 6 in docstring, should be 4 * 2 = 8 spaces, not 6

WARNING - griffe: smart_control/reinforcement_learning/scripts/populate_starter_buffer.py:45: No type or annotation for parameter 'buffer_name'
WARNING - griffe: smart_control/reinforcement_learning/scripts/populate_starter_buffer.py:47: No type or annotation for parameter 'buffer_capacity'
WARNING - griffe: smart_control/reinforcement_learning/scripts/populate_starter_buffer.py:48: No type or annotation for parameter 'steps_per_run'
WARNING - griffe: smart_control/reinforcement_learning/scripts/populate_starter_buffer.py:49: No type or annotation for parameter 'num_runs'
WARNING - griffe: smart_control/reinforcement_learning/scripts/populate_starter_buffer.py:50: No type or annotation for parameter 'sequence_length'
WARNING - griffe: smart_control/reinforcement_learning/scripts/populate_starter_buffer.py:51: No type or annotation for parameter 'env_gin_config_file_path'
WARNING - griffe: smart_control/reinforcement_learning/scripts/populate_starter_buffer.py:54: No type or annotation for returned value 1

WARNING - griffe: smart_control/reinforcement_learning/scripts/train.py:62: No type or annotation for parameter 'starter_buffer_path'
WARNING - griffe: smart_control/reinforcement_learning/scripts/train.py:63: No type or annotation for parameter 'experiment_name'
WARNING - griffe: smart_control/reinforcement_learning/scripts/train.py:65: No type or annotation for parameter 'agent_type'
WARNING - griffe: smart_control/reinforcement_learning/scripts/train.py:66: No type or annotation for parameter 'train_iterations'
WARNING - griffe: smart_control/reinforcement_learning/scripts/train.py:67: No type or annotation for parameter 'collect_steps_per_iteration'
WARNING - griffe: smart_control/reinforcement_learning/scripts/train.py:69: No type or annotation for parameter 'batch_size'
WARNING - griffe: smart_control/reinforcement_learning/scripts/train.py:70: No type or annotation for parameter 'log_interval'
WARNING - griffe: smart_control/reinforcement_learning/scripts/train.py:71: No type or annotation for parameter 'eval_interval'
WARNING - griffe: smart_control/reinforcement_learning/scripts/train.py:72: No type or annotation for parameter 'num_eval_episodes'
WARNING - griffe: smart_control/reinforcement_learning/scripts/train.py:73: No type or annotation for parameter 'checkpoint_interval'
WARNING - griffe: smart_control/reinforcement_learning/scripts/train.py:74: No type or annotation for parameter 'learner_iterations'
WARNING - griffe: smart_control/reinforcement_learning/scripts/train.py:78: No type or annotation for returned value 1

WARNING - griffe: smart_control/simulator/smart_device.py:162: Failed to get 'exception: description' pair from 'exist.'
WARNING - griffe: smart_control/simulator/smart_device.py:186: Failed to get 'exception: description' pair from 'not exist.'

WARNING - griffe: smart_control/simulator/tf_simulator.py:300: No type or annotation for parameter 'shape'
```

_Originally posted by @s2t2 in https://github.com/google/sbsim/issues/86#issuecomment-2936419754_