Otherwise if GStreamer is checked out inside a directory that
has a `Cargo.toml` file, building fails with:
```
error: current package believes it's in a workspace when it's not:
current rust-project/gstreamer/subprojects/gst-devtools/dots-viewer/Cargo.toml
workspace rust-project/Cargo.toml
This may be fixable by adding `gstreamer/subprojects/gst-devtools/dots-viewer`
to the `workspace.members` array of the manifest located at: rust-project/Cargo.toml
Alternatively, to keep it out of the workspace, add the package to the `workspace.exclude`
array, or add an empty `[workspace]` table to the package's manifest.
```
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/8562>
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