checkout picolibc submodule before publishing crates (#1444)

Signed-off-by: Jorge Prendes <jorge.prendes@gmail.com>

Author: jprendes

.github/workflows/CargoPublish.yml

@@ -31,6 +31,7 @@ jobs:
         with:
           fetch-depth: 0
           fetch-tags: true
+          submodules: true
 
       - uses: hyperlight-dev/ci-setup-workflow@v1.9.0
         with: