This commit removes a legacy check for an unsupported environment
variable. This environment variable has not been supported since 1.x so
it is safe to stop checking for the existence of this setting.
Relates elastic/x-pack-elasticsearch#2048
Original commit: elastic/x-pack-elasticsearch@023230fa9e
Today we explicitly export the HOSTNAME variable from scripts. This is
probably a relic from the days when the scripts were not run on bash but
instead assume a POSIX-compliant shell only where HOSTNAME is not
guaranteed to exist. Yet, bash guarantees that HOSTNAME is set so we do
not need to set it in scripts. This commit removes this legacy.
Relates elastic/x-pack-elasticsearch#2047
Original commit: elastic/x-pack-elasticsearch@7b833e061c
Jason Tedor
Ryan Ernst