From the shellcheck man page:
> This option defaults to false only due to ShellCheck's origin as a
> remote service for checking untrusted scripts.
> It can safely be enabled for normal development.
This allows us to remove the `shellcheck source=/dev/null` workaround
in most places.
BuildFuseExt2.sh was saying it should be run under /bin/sh but it is
using bash extensions like pushd/popd, ${BASH_SOURCE[0]}, etc. So just
run it under bash to avoid any potential issues.
Bastiaan van der Plaat