ci: build using also Go 1.18, Go 1.20, and Go 1.21

Signed-off-by: Leonardo Di Donato <leodidonato@gmail.com>

.github/workflows/build.yml

@@ -8,13 +8,44 @@ on:
 
 jobs:
   build:
-    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: true
+      matrix:
+        os: [ubuntu-latest]
+        go: [
+          '1.18',
+          '1.19',
+          '1.20',
+          '1.21',
+        ]
+        include:
+          # Set the minimum Go patch version for the given Go minor
+          - go: '1.18'
+            GO_VERSION: '~1.18.0'
+          - go: '1.19'
+            GO_VERSION: '~1.19.0'
+          - go: '1.20'
+            GO_VERSION: '~1.20.0'
+          - go: '1.21'
+            GO_VERSION: '~1.21.0'
+    runs-on: ${{ matrix.os }}
+
     steps:
 
-      - name: Set up Go 1.19
+      - name: Set up Go ${{ matrix.go }}
         uses: actions/setup-go@v3
         with:
-          go-version: 1.19
+          go-version: ${{ matrix.GO_VERSION }}
+          check-latest: true
+
+      - name: Print environment
+        id: vars
+        run: |
+          printf "Using Go at $(which go) (version $(go version))\n"
+          printf "\n\nGo environment:\n\n"
+          go env
+          printf "\n\nSystem environment:\n\n"
+          env
 
       - name: Check out the source code
         uses: actions/checkout@v3
@@ -23,9 +54,9 @@ jobs:
         uses: actions/cache@v3
         with:
           path: ~/go/pkg/mod
-          key: go-${{ runner.os }}-${{ hashFiles('go.mod') }}
+          key: go-${{ runner.os }}-${{ matrix.go }}-${{ hashFiles('go.mod') }}
           restore-keys: |
-            go-${{ runner.os }}-
+            go-${{ runner.os }}-${{ matrix.go }}
 
       - name: Install Ragel 6.10
         run: sudo apt-get install -y ragel