x/build: Tricium should not enforce Go style rules on testdata/*.go

[adonovan]

The new Tricium CI system keeps pointing out that *.go files don't have a copyright header, even when they are in a testdata directory. Test data files sometimes need to be subtly invalid Go for a wide variety of reasons, and the CI system shouldn't try to make them look like production code.

[erifan]

Also include automatically generated files.

[bcmills]

I think @rsc suggested that we disable the Tricium check entirely. Its spell-checker has a number of idiosyncrasies specific to Chromium that don't really apply to Go.

[gopherbot]

Change https://go.dev/cl/508865 mentions this issue: recipes/recipes: disable tricium copyright check

[cagedmantis]

The copyright check has been temporarily disabled.