Add cors_origins variable and pass to image

See merge request !7

Move to use now-available public image

Closes uis/devops/ucam-observe/ucam-observe-remote-server#3

See merge request !6

Updates documentation with example deployment.

Add (terse) descriptions to dev outputs - these aren't really for public
consumption, mostly to keep linters happy.

Updates documentation with instructions for accessing the remote logs,
and details of how the service is kept up-to-date.

Also includes some minor dev tweaks to provide more output from the dev
infra and an output command in the pyproject.toml.

This effectively now allows the module to be used properly by other
projects.

fix: update gitlab ci versions

See merge request !5

Initial repsoitory creation

See merge request !1

Also introduces the terraform-docs hook to automatically update README
with correct documentation.