Documentation - added Microsoft.Rest as a supported source type (mi…

…crosoft#4873)

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On the winget source documentation page, there is a missing supported
source type, namely `Microsoft.Rest`.

E.g. see the Winget [troubleshooting
page](https://learn.microsoft.com/en-us/windows/package-manager/winget/troubleshooting#:~:text=%3E%20winget%20source%20add%20%2Dn%20mysource%20%2Dt%20Microsoft.REST%20%2Da%20https%3A//www.contoso.org%20%2D%2Dverbose)
which shows examples of `Microsoft.Rest` usage.


###### Microsoft Reviewers: [Open in
CodeFlow](https://microsoft.github.io/open-pr/?codeflow=https://github.com/microsoft/winget-cli/pull/4873)

doc/windows/package-manager/winget/source.md

@@ -71,6 +71,7 @@ The **add** sub-command also supports the optional **type** parameter. The **typ
 | Type  | Description |
 |--------------|-------------|
 | **Microsoft.PreIndexed.Package** | The type of source \<default>. |
+| **Microsoft.Rest** | A Microsoft REST API source. |
 
 ## list