try out another magic env var to get rust in the QEMU container

.github/workflows/pypi_upload.yml

@@ -47,6 +47,7 @@ jobs:
     env:
       CIBW_BUILD_VERBOSITY: 1
       CIBW_BEFORE_ALL_LINUX: "curl https://sh.rustup.rs -sSf | sh -s -- --default-toolchain stable -y"
+      CIBW_ENVIRONMENT: 'PATH="$PATH:$HOME/.cargo/bin"'
 
     steps:
       - name: Check out the repo