[Feature] Support getting config and model from model name and alias.

[HAOCHENYE]

What is the feature?

Currently ,get_config and get_model only support to get model by:

from mmengine.hub import get_model, get_config

cfg = get_config('mmpretrain::mae/mae_hivit-base-p16_8xb512-amp-coslr-1600e_in1k.py')
model = get_model('mmpretrain::mae/mae_hivit-base-p16_8xb512-amp-coslr-1600e_in1k.py')

To make these interfaces more friendly to use, the first argument could also be a local config path, model name or, a alias defined in metafile.

from mmengine.hub import get_model, get_config

cfg = get_config('mmpretrain::mae_vit-base-p16_8xb512-amp-coslr-300e_in1k')  # get model by model name
cfg = get_config('mmpretrain::{model alias}')  # get model by alias
cfg = get_config('/path/to/local/config')  # get model by local config

Any other context?

No response