production-helper: Fix shellcheck warnings.
production-helper: Fix shellcheck warnings.

In tools/travis/production-helper line 24:
if ! apt-get dist-upgrade -y $APT_OPTIONS; then
                             ^-- SC2086: Double quote to prevent globbing and word splitting.

In tools/travis/production-helper line 26:
    apt-get dist-upgrade -y $APT_OPTIONS
                            ^-- SC2086: Double quote to prevent globbing and word splitting.

Signed-off-by: Anders Kaseorg <087231934ba8fcf78bc142ce37d193b895ac03c4@mit.edu>

jackrzhang/zulip,dhcrzf/zulip,rht/zulip,shubhamdhama/zulip,tommyip/zulip,showell/zulip,tommyip/zulip,synicalsyntax/zulip,brainwane/zulip,brainwane/zulip,showell/zulip,eeshangarg/zulip,andersk/zulip,shubhamdhama/zulip,rht/zulip,timabbott/zulip,rht/zulip,hackerkid/zulip,zulip/zulip,synicalsyntax/zulip,rht/zulip,shubhamdhama/zulip,punchagan/zulip,shubhamdhama/zulip,timabbott/zulip,dhcrzf/zulip,showell/zulip,showell/zulip,shubhamdhama/zulip,rishig/zulip,synicalsyntax/zulip,kou/zulip,dhcrzf/zulip,rishig/zulip,kou/zulip,punchagan/zulip,synicalsyntax/zulip,rht/zulip,zulip/zulip,dhcrzf/zulip,brainwane/zulip,tommyip/zulip,brainwane/zulip,punchagan/zulip,jackrzhang/zulip,punchagan/zulip,synicalsyntax/zulip,jackrzhang/zulip,timabbott/zulip,zulip/zulip,rishig/zulip,shubhamdhama/zulip,kou/zulip,showell/zulip,kou/zulip,eeshangarg/zulip,rishig/zulip,tommyip/zulip,zulip/zulip,synicalsyntax/zulip,kou/zulip,hackerkid/zulip,showell/zulip,hackerkid/zulip,tommyip/zulip,brainwane/zulip,hackerkid/zulip,zulip/zulip,tommyip/zulip,andersk/zulip,andersk/zulip,dhcrzf/zulip,eeshangarg/zulip,timabbott/zulip,jackrzhang/zulip,kou/zulip,timabbott/zulip,punchagan/zulip,hackerkid/zulip,brainwane/zulip,andersk/zulip,rishig/zulip,andersk/zulip,rishig/zulip,andersk/zulip,tommyip/zulip,timabbott/zulip,jackrzhang/zulip,kou/zulip,dhcrzf/zulip,zulip/zulip,rishig/zulip,zulip/zulip,eeshangarg/zulip,jackrzhang/zulip,hackerkid/zulip,brainwane/zulip,shubhamdhama/zulip,andersk/zulip,timabbott/zulip,dhcrzf/zulip,synicalsyntax/zulip,hackerkid/zulip,punchagan/zulip,eeshangarg/zulip,jackrzhang/zulip,showell/zulip,punchagan/zulip,eeshangarg/zulip,eeshangarg/zulip,rht/zulip,rht/zulip