support/docker/Dockerfile: use correct ENV syntax
buildx correctly complains about our ENV lines:
3 warnings found (use docker --debug to expand):
- LegacyKeyValueFormat: "ENV key=value" should be used instead of legacy "ENV key value" format (line 21)
- LegacyKeyValueFormat: "ENV key=value" should be used instead of legacy "ENV key value" format (line 94)
- LegacyKeyValueFormat: "ENV key=value" should be used instead of legacy "ENV key value" format (line 95)
The ENV syntax is defined as ENV FOO=BAR, not ENV FOO BAR, so adjust the
Dockerfile to match to get rid of this warning.
https://docs.docker.com/reference/dockerfile/#env
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Peter Korsgaard