Update `useWindowsDnsCache` explanation to avoid confusion

[zfb132]

I've updated the useWindowsDnsCache setting description to match its literal meaning: When set to true, it uses Windows DNS cache; when false, it bypasses it.

The current documentation describes the opposite, which is counterintuitive. This might be an oversight, and this PR corrects it to prevent any confusion.

[learn-build-service-prod[bot]]

Learn Build status updates of commit ce25a4d:

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[zfb132]

1840

1844

[mattwojo]

These updates look great. Thanks for the fixes @zfb132! Resolves https://github.com/MicrosoftDocs/WSL/issues/1844