ci: update workflows and test tolerances

- Update the Go versions in GitHub Actions workflow to include version `1.18`

Signed-off-by: Bo-Yi Wu <appleboy.tw@gmail.com>

.github/workflows/go.yml

@@ -28,7 +28,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest]
-        go: [1.19, "1.20", 1.21, 1.22]
+        go: [1.18, 1.19, "1.20", 1.21, 1.22]
         include:
           - os: ubuntu-latest
             go-build: ~/.cache/go-build