PowerToys Extension: Use project build because we don't need packagereference (#46080)

<!-- Enter a brief description/summary of your PR here. What does it
fix/what does it change/how was it tested (even manually, if necessary)?
-->
## Summary of the Pull Request
At first version, tried to use the project reference instead of package
reference, while it did not work in my local environment, so used
package reference instead.

While planned to project reference for many reasons like first day
problem explosure in sdk, maintain the strict consistent winmd with the
extension host.

Hopefully to solve some of the extension not starting problem.

<!-- Please review the items on the PR checklist before submitting-->
## PR Checklist

- [ ] Closes: #xxx
<!-- - [ ] Closes: #yyy (add separate lines for additional resolved
issues) -->
- [ ] **Communication:** I've discussed this with core contributors
already. If the work hasn't been agreed, this work might be rejected
- [ ] **Tests:** Added/updated and all pass
- [ ] **Localization:** All end-user-facing strings can be localized
- [ ] **Dev docs:** Added/updated
- [ ] **New binaries:** Added on the required places
- [ ] [JSON for
signing](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ESRPSigning_core.json)
for new binaries
- [ ] [WXS for
installer](https://github.com/microsoft/PowerToys/blob/main/installer/PowerToysSetup/Product.wxs)
for new binaries and localization folder
- [ ] [YML for CI
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ci/templates/build-powertoys-steps.yml)
for new test projects
- [ ] [YML for signed
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/release.yml)
- [ ] **Documentation updated:** If checked, please file a pull request
on [our docs
repo](https://github.com/MicrosoftDocs/windows-uwp/tree/docs/hub/powertoys)
and link it here: #xxx

<!-- Provide a more detailed description of the PR, other things fixed,
or any additional comments/features here -->
## Detailed Description of the Pull Request / Additional comments

<!-- Describe how you validated the behavior. Add automated tests
wherever possible, but list manual validation steps taken as well -->
## Validation Steps Performed

Built an installer and validated in my arm64 and x64 machine, works
perfectly

Author: vanzue

Directory.Packages.props

@@ -40,7 +40,6 @@
     <!-- Including MessagePack to force version, since it's used by StreamJsonRpc but contains vulnerabilities. After StreamJsonRpc updates the version of MessagePack, we can upgrade StreamJsonRpc instead. -->
     <PackageVersion Include="MessagePack" Version="3.1.3" />
     <PackageVersion Include="Microsoft.CodeAnalysis.NetAnalyzers" Version="9.0.0" />
-    <PackageVersion Include="Microsoft.CommandPalette.Extensions" Version="0.9.260303001" />
     <PackageVersion Include="Microsoft.Data.Sqlite" Version="9.0.10" />
     <!-- Including Microsoft.Bcl.AsyncInterfaces to force version, since it's used by Microsoft.SemanticKernel. -->
     <PackageVersion Include="Microsoft.Bcl.AsyncInterfaces" Version="9.0.10" />

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.PowerToys/Microsoft.CmdPal.Ext.PowerToys.csproj

@@ -38,7 +38,6 @@
 
 	<ItemGroup>
 		<PackageReference Include="Microsoft.WindowsAppSDK" />
-		<PackageReference Include="Microsoft.CommandPalette.Extensions" />
 		<PackageReference Include="Microsoft.Windows.CsWin32">
 			<PrivateAssets>all</PrivateAssets>
 			<IncludeAssets>runtime; build; native; contentfiles; analyzers</IncludeAssets>
@@ -56,6 +55,7 @@
 	</PropertyGroup>
 
 	<ItemGroup>
+		<ProjectReference Include="..\..\extensionsdk\Microsoft.CommandPalette.Extensions.Toolkit\Microsoft.CommandPalette.Extensions.Toolkit.csproj" />
 		<ProjectReference Include="..\..\..\..\common\ManagedCommon\ManagedCommon.csproj" />
 		<ProjectReference Include="..\..\..\..\common\Common.Search\Common.Search.csproj" />
 		<ProjectReference Include="..\..\..\..\common\Common.UI\Common.UI.csproj" />