Configuration Binder source generator creates namespace ambiguity and not found error

[ciaozhang]

Description
When trying to use the Configuration Binder source generator in Microsoft.IdentityModel.S2S.DstsExtensions project, I'm getting compile errors.
Branch: https://identitydivision.visualstudio.com/DevEx/_git/Microsoft-IdentityModel-S2S/commit/57acb8a13628371366f73cb0730d3f7abe8a712a?refName=refs%2Fheads%2FXiao%2FTrimDsts

Reproduction Steps
build Microsoft.IdentityModel.S2S.DstsExtensions project with VS

Expected behavior
The project should build successfully.

Actual behavior
There are 3build errors:

Here is the generated code:

https://microsoft-my.sharepoint-df.com/:w:/p/zhangxia/EQOQ4EWvfOdLoTSeUkg552wBEdsfceiutcTixc-Sg_xVgA?e=pOfPuJ

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[tarekgh]

@ciaozhang I didn't try it yet but maybe it is worth trying the configuration package v9.0.0. We have fixed some issues like https://github.com/dotnet/runtime/issues?q=is%3Aissue%20label%3Aarea-Extensions-Configuration%20label%3Asource-generator%20CredentialDescription.

[tarekgh]

CC @ericstj @eerhardt