Pass environment variable from host to runner

GitLab CI/CD
1

Hello. Is there a way to pass environment variable from host to runner?

I can set it directly:

config.toml

[[runners]]
  environment = [
    "http_proxy=http://proxy.example.com:3128",
  ]

but I would like to assign a current value from host. Something like:

[[runners]]
  environment = [
    "http_proxy",
  ]

or

[[runners]]
  environment = [
    "http_proxy=${http_proxy}",
  ]