Improve env:install command with better configurability and error handling

[westonruter]

Trac ticket: https://core.trac.wordpress.org/ticket/63543

• Force WP-CLI to use the the wp-config.php in the directory above the src directory via the WP_CONFIG_PATH environment variable read by WP-CLI in the wp_locate_config() function.
• Update the env:install command to write out the config at the repo root instead of writing it inside of the ABSPATH only then to move it one directory up.
• Fix JSHint issues.
• Add error handling to when npm run env:install is executed without having first done npm run env:start (which has tripped me up multiple times), in which case the script will end with an exit code of 1 and emit:

Error: It appears the development environment has not been started. Message: Timed out waiting for: tcp:localhost:8000
Did you forget to do 'npm run env:start'?

Commit Message

Build/Test Tools: Improve env:install command with better configurability and error handling.

• Force WP-CLI to use the the wp-config.php in the directory above the src directory via the WP_CONFIG_PATH environment variable read by WP-CLI in the wp_locate_config() function.
• Update the env:install command to write out the config at the repo root instead of writing it inside of the ABSPATH only then to move it one directory up.
• Fix JSHint issues.
• Add error handling to when npm run env:install is executed without having first done npm run env:start (which has tripped me up multiple times), in which case the script will end with an exit code of 1 and emit:

Error: It appears the development environment has not been started. Message: Timed out waiting for: tcp:localhost:8000
Did you forget to do 'npm run env:start'?

Fixes #63543.
Props westonruter, jorbin, SirLouen.

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Props westonruter, jorbin.

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[github-actions]

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[aaronjorbin]

One suggested change, otherwise this looks good to me.

[github-actions]

A commit was made that fixes the Trac ticket referenced in the description of this pull request.

SVN changeset: 60305
GitHub commit: 6ac0efd

This PR will be closed, but please confirm the accuracy of this and reopen if there is more work to be done.