Can't use UseGlobalNodeJsExtensionsNpmPackage when used from NuGet (OSOE-914)

[Piedone]

When the project is used from NuGet, using the below config:

<UseGlobalNodeJsExtensionsNpmPackage>true</UseGlobalNodeJsExtensionsNpmPackage>
<NodeJsExtensionsNpmPackageSourcePath>$(MSBuildThisFileDirectory)node_modules/.nx</NodeJsExtensionsNpmPackageSourcePath>

Will result in a build error like:

ΓÇëERR_PNPM_NO_IMPORTER_MANIFEST_FOUNDΓÇë No package.json (or package.yaml, or package.json5) was found in "path\to\solution\node_modules/.nx".

This should still work, like it does when using the project as a submodule.

Configure the NuGetTest solution like this too. Currently, it disables UseGlobalNodeJsExtensionsNpmPackage deliberately (as does Lombiq.NodeJs.Extensions.Samples.NuGet, but it needs that, see the comment there). Make the Lombiq.OSOCE.NuGet.TestTheme theme there use NE to build the trivial SCSS file that's actually already there, but that doesn't do anything.

Jira issue

[Piedone]

Perhaps something you'd be interested in, @sarahelsaig?