Update github action

- Use latest version of checkout action.
- Checkout the head of the PR commit.
- Install json-c dependency.

Signed-off-by: Alex Jaramillo <[email protected]>

Author: alexjch

.github/workflows/ccpp.yml

@@ -8,9 +8,11 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v4
+      with:
+        ref: ${{ github.event.pull_request.head.sha }}
     - name: install dependencies
-      run: sudo apt-get install libcurl4-gnutls-dev valgrind libelf-dev libdw-dev
+      run: sudo apt-get install libcurl4-gnutls-dev valgrind libelf-dev libdw-dev libjson-c-dev
     - name: install check
       run: wget https://github.com/libcheck/check/releases/download/0.12.0/check-0.12.0.tar.gz &&
            tar xf check-0.12.0.tar.gz &&