No workspace package paths are detected on Windows

I was trying to setup [ardatan/graphql-tools ](https://github.com/ardatan/graphql-tools), but running `yarn build` did not output `√ Built graphql-tools`, instead an error was thrown by the postinstall script because the build files were not found.

I found out that the util function `getWorkspacePackagePaths` returns an empty array. This is because the glob pattern is resolved with a `path.join` call in it, when it should instead be `path.posix.join`, as glob patterns can only contain forward slashes (see https://github.com/sindresorhus/globby?tab=readme-ov-file#api).