Update headers.md

[nacharya1]

Updated link to create subscription from Cogs servs to Azure Portal

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

Learn Build status updates of commit c20bb47:

:warning: Validation status: warnings

File	Status	Preview URL	Details
bing-docs/bing-custom-search/reference/headers.md	:warning:Warning	View	Details

bing-docs/bing-custom-search/reference/headers.md

• Line 2, Column 1: [Warning: ms-author-missing - See documentation] Missing required attribute: 'ms.author'. Add the current author's Microsoft alias.

For more details, please refer to the build report.

Note: Your PR may contain errors or warnings or suggestions unrelated to the files you changed. This happens when external dependencies like GitHub alias, Microsoft alias, cross repo links are updated. Please use these instructions to resolve them.

For any questions, please:

• Try searching the learn.microsoft.com contributor guides
• Post your question in the Learn support channel

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

Learn Build status updates of commit 5d29a74:

:warning: Validation status: warnings

For more details, please refer to the build report.

Note: Your PR may contain errors or warnings or suggestions unrelated to the files you changed. This happens when external dependencies like GitHub alias, Microsoft alias, cross repo links are updated. Please use these instructions to resolve them.

For any questions, please:

• Try searching the learn.microsoft.com contributor guides
• Post your question in the Learn support channel