Add API support for env-dut files

Add necessary API for handling env-dut files.
Fix in the same time remaining env.dut.yaml reference
Tested with https://git.lavasoftware.org/montjoie/lavacli/-/tree/env-dut

Signed-off-by: Corentin LABBE <clabbe@baylibre.com>
16 jobs for env-dut in 16 minutes and 36 seconds (queued for 2 seconds)
Status Name Job ID Coverage
  Test
passed dispatcher-debian-10 #127085
amd64

00:02:27

passed dispatcher-debian-11 #127087
amd64

00:02:29

passed server-debian-10 #127086
amd64

00:03:04

passed server-debian-11 #127088
amd64

00:05:32

 
  Analyze
passed bandit-sast #127089
amd64-dind

00:00:54

passed black #127090
amd64

00:00:34

passed code_quality #127091
amd64

00:00:21

passed codespell #127096
amd64

00:00:17

passed coverage #127092
amd64

00:06:48

61.01%
passed dockerfiles #127093
amd64

00:00:16

passed pylint #127095
amd64

00:03:04

passed schemas #127094
amd64

00:00:29

 
  Build
passed debian/10 #127098
amd64

00:01:14

passed doc #127097
amd64

00:00:36

passed docker-amd64-dispatcher #127099
amd64-dind

00:04:02

passed docker-amd64-server #127100
amd64-dind

00:04:11