Remove problematic language from Jetpack selector and documentation

[sarayourfriend]

Changes proposed in this Pull Request

• Rename isJetpackUserMaster to isJetpackUserConnectionOwner
• Update a comment to remove problematic language
• Fix a linting error

Testing instructions

I'm still unclear on these, trying to get verification of exactly how this is.

• Using an external site that is connected to Calypso via Jetpack, navigate to the "connection settings" and verify that with the correct user you see that you are either an owner or not the owner of the connection.
• Ensure unit tests still pass

Part of #43395

[matticbot]

Test live: https://calypso.live/?branch=update/remove-problematic-language-master

[matticbot]

Here is how your PR affects size of JS and CSS bundles shipped to the user's browser:

Sections (~1 bytes added 📈 [gzipped])

name      parsed_size           gzip_size
settings        +18 B  (+0.0%)       +1 B  (+0.0%)

Sections contain code specific for a given set of routes. Is downloaded and parsed only when a particular route is navigated to.

Legend

What is parsed and gzip size?

Parsed Size: Uncompressed size of the JS and CSS files. This much code needs to be parsed and stored in memory.
Gzip Size: Compressed size of the JS and CSS files. This much data needs to be downloaded over network.

Generated by performance advisor bot at iscalypsofastyet.com.

[wp-desktop]

WordPress Desktop CI Failure for job "wp-desktop-source".

@saramarcondes please inspect this job's build steps for breaking changes at this link. For temporal failures, you may try to "Rerun Workflow from Failed".

Please also ensure this branch is rebased off latest Calypso.

wp-desktop ci passing, closing review

[sarayourfriend]

Duplicate of #43788