All changes in this patch were performed automatically with `shfmt` with
configuration flags specified in `.pre-commit-config.yaml`.
In addition to fixing whitespace the roundtrip through shfmt's AST also
transforms command substitutions
`cmd`
# becomes
$(cmd)
and some redirects
>&2 echo "msg"
# becomes
echo >&2 "msg"
The initialization of the private testsuite currently fails builds run in
forks. Cirrus's encrypted variables won't work outsize of the Zeek project, so
skip that setting altogether.
