Improve C2751

[Rageking8]

Fix a few issues:

• Missing /c flag
• Adding definitions to the std namespace is UB
• Superfluous C2955 (use of class template requires template argument list) error

Overall, the example is now slightly simpler.

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Learn Build status updates of commit a4290ab:

✅ Validation status: passed

File	Status	Preview URL	Details
docs/error-messages/compiler-errors-2/compiler-error-c2751.md	✅Succeeded

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PRMerger Results

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

[TylerMSFT]

Thank you for the improvement.

[TylerMSFT]

#sign-off