Add a subcommand to jina hub to show the local location of Jina Executor

[JoanFM]

Ref: https://jinaai.slack.com/archives/C023A7RAPGR/p1645808202058109

[JoanFM]

Coming from https://github.com/jina-ai/internal-tasks/issues/398

[floralatin]

• [x] jina-hubble-sdk: https://github.com/jina-ai/jina-hubble-sdk/pull/85
• [x] jina-core https://github.com/jina-ai/jina/pull/5282

[floralatin]

optimization:

• [x] Improve the print style.
• [ ] Investigate using disk_cache.db to display images

[floralatin]

@mapleeit After the investigation, we can't get the executor info from the disk_cache.db. As shown in the figure, we download different versions of an executor, and the file disk_cache.db will record it. So if we want to know the real downloaded version of this executor, we just need to parse the */*.dist-info file and config.yml file.

Butdisk_cache.db can be used as auxiliary information, to get the docker image of the tag corresponding to the executor.

[mapleeit]

@floralatin I see. Then maybe we can't count on the data in disk_cache.db.

Don't list jinahub+docker:// for now then, user can use docker images and find something anyway.

[floralatin]

@mapleeit OK, I will just improve the print result of hub list.