Add Go 1.20 to the test matrix

Author: dveeden

.github/workflows/ci.yml

@@ -5,7 +5,7 @@ jobs:
   test:
     strategy:
       matrix:
-        go: [ 1.19, 1.18, 1.17, 1.16 ]
+        go: [ 1.20, 1.19, 1.18, 1.17, 1.16 ]
         os: [ ubuntu-22.04, ubuntu-20.04 ]
     name: Tests Go ${{ matrix.go }} # This name is used in main branch protection rules
     runs-on: ${{ matrix.os }}