Build using different php versions.

Author: kirmorozov

.github/workflows/c-cpp.yml

@@ -8,17 +8,21 @@ on:
 
 jobs:
   build:
-
-    runs-on: ubuntu-latest
-
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ ubuntu-16.04, ubuntu-latest ]
+        php: [ '7.4', '8.0' ]
     steps:
     - uses: actions/checkout@v2
     - name: install PHP
       run: > 
           sudo apt install software-properties-common && \
           sudo add-apt-repository ppa:ondrej/php && \
           sudo apt-get update \
-          sudo apt-get install php7.4 php7.4-dev
+          sudo apt-get install php$PHP_VERSION php$PHP_VERSION-dev
+      env:
+        PHP_VERSION: ${{ matrix.php }}
     - name: make
       run: make
     - name: make install