actions: downgrade Elixir version

Signed-off-by: Matteo Cafasso <[email protected]>

Author: noxdafox

.github/workflows/action.yml

@@ -18,7 +18,7 @@ jobs:
           sudo apt install -y --allow-downgrades esl-erlang=${{ matrix.erlang }}
       - name: Install Elixir
         run: |
-          sudo apt install -y elixir
+          sudo apt install -y elixir=1.12.2-1
       - name: Run tests
         run: |
           make tests