docs: add documentation for useTarget hook/feature

[nmerget]

Description

closes #1209

Please provide the following information:

• What changes you made:

Add documentation for useTarget

• Why you made them, and:

It was missing ^.^

Make sure to follow the PR preparation steps in CONTRIBUTING.md before submitting your PR:

• format the codebase: from the root, run yarn fmt:prettier.
• update all snapshots (in core & CLI): from the root, run yarn test:update
• add Changeset entry: from the root, run yarn g:changeset and follow the CLI instructions. Alternatively, use the Changeset Github Bot to create the file.

[changeset-bot]

⚠️ No Changeset found

Latest commit: ce6027a

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

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