create-zulip-admin: Fix shellcheck warnings.
create-zulip-admin: Fix shellcheck warnings.

In scripts/lib/create-zulip-admin line 3:
if ([ "$ZULIP_USER_CREATION_ENABLED" == "True" ] || [ "$ZULIP_USER_CREATION_ENABLED" == "true" ]) && \
   ^-- SC2235: Use { ..; } instead of (..) to avoid subshell overhead.

In scripts/lib/create-zulip-admin line 4:
   ([ -z "$ZULIP_USER_DOMAIN" ]   || \
   ^-- SC2235: Use { ..; } instead of (..) to avoid subshell overhead.

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

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