Improve C2469 error reference

[Rageking8]

• Change error message to one with explicit reference to new and void as it seems newer (commit 062031c added this variant to the index page, while the older one is there since the first commit in 2016) and the error does not seem to apply to anything other than operator new with type void.
• Add "Remarks" heading and tweak its contents to reflect the new error message.
• Overhaul the existing example and add a new one based on the user's intent (i.e. they specified the wrong allocation type versus they made an invalid attempt to allocate untyped memory (see c++ - Using new on void pointer - Stack Overflow)).
• Update metadata

[prmerger-automator]

@Rageking8 : Thanks for your contribution! The author(s) and reviewer(s) have been notified to review your proposed change.

[learn-build-service-prod]

Learn Build status updates of commit 72165c3:

✅ Validation status: passed

File	Status	Preview URL	Details
docs/error-messages/compiler-errors-1/compiler-error-c2469.md	✅Succeeded

For more details, please refer to the build report.

[prmerger-automator]

PRMerger Results

Issue	Description
File Change Percent	This PR contains file(s) with more than 30% file change.

[ttorble]

@TylerMSFT

Can you review the proposed changes?

IMPORTANT: When the changes are ready for publication, adding a #sign-off comment is the best way to signal that the PR is ready for the review team to merge.

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

[TylerMSFT]

Thank you for improving the topic.

[TylerMSFT]

#sign-off

[learn-build-service-prod]

Learn Build status updates of commit 6df3251:

✅ Validation status: passed

File	Status	Preview URL	Details
docs/error-messages/compiler-errors-1/compiler-error-c2469.md	✅Succeeded

For more details, please refer to the build report.

[prmerger-automator]

PRMerger Results

Issue	Description
File Change Percent	This PR contains file(s) with more than 30% file change.

[TylerMSFT]

#sign-off