static/templates/stream_settings_checkbox: Simplify handlebar logic.
static/templates/stream_settings_checkbox: Simplify handlebar logic.

Fixes #12801

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