garble/testdata
Daniel Martí b71ff42877
testdata: remove some unnecessary execs ()
Our use of go-internal's gotooltest.Setup means that "go" is set up as a
top-level command in the scripts, so we can simply "go build" instead of
having to "exec go build". The result is practically the same, but the
scripts are simpler.

While at it, I had left an "exec cat" behind; remove it.
..
bench set up an AUTHORS file to attribute copyright
mod make the handling of import paths more robust
scripts testdata: remove some unnecessary execs ()