Try to use submodules

Signed-off-by: Adrien Gallouët <adrien@gallouet.fr>

.github/workflows/build.yml

@@ -1,4 +1,4 @@
-name: C/C++ CI
+name: Build
 
 on: [push]
 
@@ -12,8 +12,9 @@ jobs:
 
     steps:
     - uses: actions/checkout@v1
+      with:
+          submodules: true
     - name: Build glorytun
       run: |
-          git submodule update --init --recursive
           ./sodium.sh
           make