Update golangci-lint image to Go 1.14 to eliminate unnecessary warnings
## Summary
This image: registry.gitlab.com/gitlab-org/gitlab-build-images:golangci-lint-alpine
This is recommended as the way to perform linting of Go projects in the Gitlab CI documentation, here: https://docs.gitlab.com/ee/development/go_guide/#automatic-linting
The problem is that the image is based on a Go version that does not include `*testing.T Cleanup()` (Go 1.13?) It should be updated to Go 1.14 to support current developer workflow.
Projects using `*testing.T Cleanup()` will have warnings generated during linting.
## Improvements
Update the Go version in the image to Go 1.14
Optionally, provide multiple versions of the image with current releases of Go.
## Risks
This seems pretty low risk given that all it is used for is linting code
## Involved components
I think the image is the only component
issue