Bump CI

Author: jaspervdj

.github/workflows/ci.yml

@@ -19,7 +19,7 @@ jobs:
 
     - uses: actions/checkout@v2
 
-    - uses: actions/[email protected].2
+    - uses: actions/[email protected].4
       name: Setup Haskell Stack
       with:
         ghc-version: ${{ matrix.ghc }}
@@ -32,7 +32,7 @@ jobs:
         key: ${{ runner.os }}-${{ matrix.ghc }}-v3
 
     - name: Add ~/.local/bin to PATH
-      run: echo "::add-path::$HOME/.local/bin"
+      run: echo "$HOME/.local/bin" >> $GITHUB_PATH
 
     - name: Build
       run: make build