Fix typo and add link

[CrazyTim]

Issues:

• Fix typo (missing 's')
• Add link to the definition on learn.microsoft.com

For example, currently it is this:

Don't use this method in ASP.NET Core: rather use: services.AddInMemoryTokenCache() in ConfigureServices.

Please change to this:

Don't use this method in ASP.NET Core: rather use: services.AddInMemoryTokenCaches() in ConfigureServices.

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Document Details

⚠ Do not edit this section. It is required for learn.microsoft.com ➟ GitHub issue linking.

• ID: 47a9f34a-a96e-e065-ff1e-fd9331df147b
• Version Independent ID: 47a9f34a-a96e-e065-ff1e-fd9331df147b
• Content: TokenCacheExtensions.AddInMemoryTokenCache Method (Microsoft.Identity.Web) - Microsoft Authentication Library for .NET
• Content Source: dotnet/xml/Microsoft.Identity.Web/TokenCacheExtensions.xml
• Service: msal
• GitHub Login: @dotnet-bot
• Microsoft Alias: dmwendia