ref: multi-experiment support for `exp push/pull`

[dberenbaum]

Please update https://dvc.org/doc/command-reference/exp/push and pull (and any other refs. affected) but please create an issue still so we can check whether other docs need updates too.

Originally posted by @jorgeorpinel in treeverse/dvc#7206 (comment)

p.s. related to treeverse/dvc#5489

[jorgeorpinel]

• I guess other than thee cmd ref. we may need to update https://dvc.org/doc/user-guide/experiment-management/sharing-experiments cc @iesahin want to take that part?

[dberenbaum]

• Also we can get rid of https://dvc.org/doc/user-guide/how-to/share-many-experiments.

[karajan1001]

we may need to update https://dvc.org/doc/user-guide/experiment-management/sharing-experiments

related to treeverse/dvc#5489