Added a note about MSStoreProductIdentifier non-support to RestInterface_1_1.cpp. - #6458

📖 Description

The following section in https://github.com/microsoft/winget-cli/blob/master/src/AppInstallerCLITests/RestInterface_1_1.cpp claims that the following would be able to get working in a manifest:

(...)
{
  "Architecture": "x64",
  "InstallerType": "msstore",
  "MSStoreProductIdentifier": "9nblggh4nns1"
}
(...)

It can't.

So this PR adds a note about that it can't.

🔗 References

• Trying out the "msstore" installer type: Ubisoft.Connect version 172.1.0.13247 winget-pkgs#416200

🔍 Validation

Added a secondary installer to a manifest that used the syntaxing used for the msstore InstallerType in https://github.com/microsoft/winget-cli/blob/master/src/AppInstallerCLITests/RestInterface_1_1.cpp

✅ Checklist

• Signed the Contributor License Agreement
• Linked to an issue
• Updated Release Notes (if applicable)
• Updated documentation (if applicable)
• Updated Copilot instructions (if build, architecture, or conventions changed)

📋 Issue Type

• Bug fix
• Feature
• Task

Microsoft Reviewers: Open in CodeFlow