Fixing GH actions

Author: akoutmos

.github/workflows/main.yml

@@ -26,16 +26,16 @@ jobs:
         uses: actions/cache@v2
         with:
           path: deps
-          key: ${{ runner.os }}-mix-${{ hashFiles('**/mix.lock') }}
-          restore-keys: ${{ runner.os }}-mix-
+          key: ${{ runner.os }}-mix-v2-${{ hashFiles('**/mix.lock') }}
+          restore-keys: ${{ runner.os }}-mix-v2-
       - name: Install dependencies
         run: mix deps.get
       - name: Restore PLT cache
         uses: actions/cache@v2
         with:
           path: priv/plts
-          key: ${{ runner.os }}-mix-${{ hashFiles('**/mix.lock') }}
-          restore-keys: ${{ runner.os }}-mix-
+          key: ${{ runner.os }}-mix-v2-${{ hashFiles('**/mix.lock') }}
+          restore-keys: ${{ runner.os }}-mix-v2-
       - name: Mix Formatter
         run: mix format --check-formatted
       - name: Check for compiler warnings
@@ -72,8 +72,8 @@ jobs:
         uses: actions/cache@v2
         with:
           path: deps
-          key: ${{ runner.os }}-mix-${{ hashFiles('**/mix.lock') }}
-          restore-keys: ${{ runner.os }}-mix-
+          key: ${{ runner.os }}-mix-v2-${{ hashFiles('**/mix.lock') }}
+          restore-keys: ${{ runner.os }}-mix-v2-
       - name: Install dependencies
         run: mix deps.get
       - name: ExUnit tests