incorrect naming of key in metatdata. 'experiment_container_id' should be 'ophys_container_id'

[DowntonCrabby]

Describe the bug Currently there is a metadata key called 'experiment_container_id' which should be 'ophys_container_id' to be consistent with the naming across the rest of the sdk

To Reproduce

from allensdk.brain_observatory.behavior.behavior_project_cache import VisualBehaviorOphysProjectCache as bpc
cache_dir = r'\\allen\programs\braintv\workgroups\nc-ophys\visual_behavior\platform_paper_cache' 
cache = bpc.from_s3_cache(cache_dir=cache_dir)

ophys_experiment = cache.get_behavior_ophys_experiment(selected_ophys_experiment_id)
ophys_experiment.metadata.keys()

Expected behavior I would expect a key called 'ophys_container_id'

Actual Behavior instead there is a key called 'experiment_container_id'

Environment (please complete the following information):

• windows
• Python 3.7
• AllenSDK version 2.12.2

Additional context This only occurs in the metadata of behavior ophys experiment dataset and not the behavior session dataset

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