Ignore whitespace when checking start of JOB_ROUTER_DEFAULTS. #6128
Ignore whitespace when checking start of JOB_ROUTER_DEFAULTS. #6128

When checking whether the first character of JOB_ROUTER_DEFAULTS is an
open bracket, skip any leading whitespace. With empty macro
substitutions, config values can have leading whitespace.

htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor