Build all variants like Travis CI

GitHub Actions cancel all in-progress jobs if any matrix job fails.
This behavior makes investigating version-specific issues (e.g. #406)
harder.

Signed-off-by: Kazuyoshi Kato <[email protected]>

Author: kzys

.github/workflows/build.yaml

@@ -18,6 +18,8 @@ jobs:
     strategy:
       matrix:
         go: ['1.11', '1.12', '1.13', '1.14']
+      # Build all variants regardless of failures
+      fail-fast: false
     name: Go ${{ matrix.go }}
 
     steps: