add jpeg quality option

[cabreraalex]

Description of changes:

Adds option for JPEG quality.

Issue #, if available:

• Fixes Choose JPEG compression level #811

Merge Checklist:

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[karan6181]

Hey @cabreraalex , thanks for creating a PR. One minor comment, can you please update your PR with the changes that are not relevant to this PR? Seems like there are some spacing changes, single/double quotes changes, etc.

[cabreraalex]

oops yup, done

[snarayan21]

@cabreraalex Thanks for adding this! Would be great to have a unit test for this functionality as well before merging.

[snarayan21]

@cabreraalex Mind addressing the review comments when you have some time? Thanks!

[cabreraalex]

AFAI can tell just the config is passed, e.g. from jpeg:12 only the 12 is passed to from_str:

streaming/streaming/base/format/mds/encodings.py

Line 591 in 45c2132

def _get_coder(encoding: str) -> Optional[Encoding]:

There is no formal type for the quality, just integer

[ethantang-db]

We should probably also add a test for this too then, to also confirm what it should look like when used. Thanks!

[snarayan21]

@cabreraalex Mind adding the test that @ethantang-db mentioned and we can get this in?