Update const-cpp.md

[science-enthusiast]

More clarity about extern const in C and C++: declaration, definition etc.

[prmerger-automator]

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[learn-build-service-prod]

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[Court72]

@TylerMSFT

Can you review the proposed changes?

When the changes are ready for publication, add a #sign-off comment to signal that the PR is ready for the review team to merge.

#label:"aq-pr-triaged"
@MicrosoftDocs/public-repo-pr-review-team

[Court72]

#label:"aq-pr-triaged"

[prmerger-automator]

@science-enthusiast : Thanks for your contribution! The author(s) have been notified to review your proposed change.

[TylerMSFT]

Thank you for these updates. They 'definitely' (pun intended) clarify things ;-)

[TylerMSFT]

#sign-off

[prmerger-automator]

@science-enthusiast : Thanks for your contribution! The author(s) have been notified to review your proposed change.