fix: use needs in message to mach with documentation

[snitin315]

What kind of change does this PR introduce?
Fix #18814

Refer webpack/webpack.js.org#7402 (comment)

needs is grammatically correct.

Did you add tests for your changes?
Yes

Does this PR introduce a breaking change?
No

What needs to be documented once your changes are merged?
No

[webpack-bot]

For maintainers only:

• This needs to be documented (issue in webpack/webpack.js.org will be filed when merged)
• This needs to be backported to webpack 4 (issue will be created when merged)