workflows: update go version

.github/workflows/go.yml

@@ -1,28 +1,28 @@
 name: Go Tests
 on: [push, pull_request]
 jobs:
-  test-1_18:
-    name: Test 1.18
+  test-1_19:
+    name: Test 1.19
     runs-on: ubuntu-latest
     steps:
-      - name: Set up Go 1.18
+      - name: Set up Go 1.19
         uses: actions/setup-go@v4
         with:
-          go-version: 1.18
+          go-version: '1.19'
         id: go
       - name: Check out code
         uses: actions/checkout@v3
       - name: Test
         run: go test -v ./...
 
-  test-1_19:
-    name: Test 1.19
+  test-1_20:
+    name: Test 1.20
     runs-on: ubuntu-latest
     steps:
-      - name: Set up Go 1.19
+      - name: Set up Go 1.20
         uses: actions/setup-go@v4
         with:
-          go-version: 1.19
+          go-version: '1.20'
         id: go
       - name: Check out code
         uses: actions/checkout@v3