Fix typo Slides instead of Sheets in PowerPoint docs

[scottmcarthur]

how-to-retrieve-the-number-of-slides-in-a-presentation-document.md

Changes Sheets to Slides (structure was probably copied from Excel documentation.)

[o365devx]

Docs Build status updates of commit 09b1b71:

⚠️ Validation status: warnings

File	Status	Preview URL	Details
docs/how-to-retrieve-the-number-of-slides-in-a-presentation-document.md	⚠️Warning		Details

docs/how-to-retrieve-the-number-of-slides-in-a-presentation-document.md

• Line 26: [Warning-insecure-link] Link 'http://www.microsoft.com/en-us/download/details.aspx?id=30425' is insecure. Links to Microsoft sites must use 'https' instead of 'http'.
• Line 90: [Warning-hard-coded-locale] Link 'https://msdn.microsoft.com/en-us/library/office/documentformat.openxml.packaging.presentationdocument.open.aspx' contains locale code 'en-us'. For localizability, remove 'en-us' from links to most Microsoft sites.
• Line 93: [Warning-hard-coded-locale] Link 'https://msdn.microsoft.com/en-us/library/office/documentformat.openxml.packaging.presentationdocument.presentationpart.aspx' contains locale code 'en-us'. For localizability, remove 'en-us' from links to most Microsoft sites.
• Line 123: [Warning-hard-coded-locale] Link 'https://msdn.microsoft.com/en-us/library/office/documentformat.openxml.packaging.presentationpart.slideparts.aspx' contains locale code 'en-us'. For localizability, remove 'en-us' from links to most Microsoft sites.
• Line 151: [Warning-hard-coded-locale] Link 'https://msdn.microsoft.com/en-us/library/office/documentformat.openxml.presentation.slide.show.aspx' contains locale code 'en-us'. For localizability, remove 'en-us' from links to most Microsoft sites.
• Line 158: [Warning-insecure-link] Link 'http://msdn2.microsoft.com/EN-US/library/bb301979' is insecure. Links to Microsoft sites must use 'https' instead of 'http'.

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[ghost]

All CLA requirements met.

[o365devx]

Docs Build status updates of commit 8148b1a:

⚠️ Validation status: warnings

File	Status	Preview URL	Details
docs/how-to-retrieve-the-number-of-slides-in-a-presentation-document.md	⚠️Warning		Details

docs/how-to-retrieve-the-number-of-slides-in-a-presentation-document.md

• Line 26: [Warning-insecure-link] Link 'http://www.microsoft.com/download/details.aspx?id=30425' is insecure. Links to Microsoft sites must use 'https' instead of 'http'.

For more details, please refer to the build report.

If you see build warnings/errors with permission issues, it might be due to single sign-on (SSO) enabled on Microsoft's GitHub organizations. Please follow instructions here to re-authorize your GitHub account to Docs Build.

Note: Broken links written as relative paths are included in the above build report. For broken links written as absolute paths or external URLs, see the broken link report.

Note: Your PR may contain errors or warnings 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 in the Docs contributor and Admin Guide
• See the frequently asked questions
• Post your question in the Docs support channel

[o365devx]

Docs Build status updates of commit 1422520:

✅ Validation status: passed

File	Status	Preview URL	Details
docs/how-to-retrieve-the-number-of-slides-in-a-presentation-document.md	✅Succeeded

For more details, please refer to the build report.

Note: Broken links written as relative paths are included in the above build report. For broken links written as absolute paths or external URLs, see the broken link report.

For any questions, please:

• Try searching in the Docs contributor and Admin Guide
• See the frequently asked questions
• Post your question in the Docs support channel