Update and use last 3 major versions for CI builds (#177)

Author: deckarep

.github/workflows/ci.yml

@@ -4,7 +4,7 @@ jobs:
   test:
     strategy:
       matrix:
-        go-version: [1.20.x, 1.21.x, 1.22.x, 1.23.x, 1.24.x]
+        go-version: [1.24.x, 1.25.x, 1.26.x]
         os: [ubuntu-latest, macos-latest, windows-latest]
     runs-on: ${{ matrix.os }}
     steps: