Tests, Docs: Remove references to dops-components

[ockham]

Changes proposed in this Pull Request:

Remove some references to (now-defunct) dops-components. Among other things, their npm's path was still added to NODE_PATH for some of our tests. Furthermore, some docs still had references to dops-components.

Discovered while working on #12381.

Is this a new feature or does it add/remove features to an existing part of Jetpack?

N/A

Testing instructions:

Production code isn't affected. Try running updated tests though:

yarn test-client
yarn test-gui
yarn test-modules

Proposed changelog entry for your changes:

• Tests, Docs: Remove references to dops-components

[matticbot]

Caution: This PR has changes that must be merged to WordPress.com
Hello ockham! These changes need to be synced to WordPress.com - If you 're an a11n, please commandeer, review, and approve D28260-code before merging this PR. Thank you!

[jetpackbot]

Thank you for the great PR description!

When this PR is ready for review, please apply the [Status] Needs Review label. If you are an a11n, please have someone from your team review the code if possible. The Jetpack team will also review this PR and merge it to be included in the next Jetpack release.

Scheduled Jetpack release: June 4, 2019.
Scheduled code freeze: May 28, 2019

Generated by 🚫 dangerJS against 64a3c5c

[jeherve]

Nice find! This looks good to me. 🚢