chroot_version_hooks.d: trim world set

Some of our update_chroot steps would add packages to this that we
didn't want and would later cause rebuild issues.  Throw it away.

BUG=chromium:1013967
TEST=`./update_chroot` passes

Change-Id: I87d83e7be6dd6f81b96fea1cbaab0f19d65d2a8b
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosutils/+/1860039
Tested-by: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Chris McDonald <cjmcdonald@chromium.org>
1 file changed