Revert "Switch ci to byzantium"

We want amber-phone

This reverts commit c5767f5d.

.gitlab-ci.yml

@@ -5,7 +5,6 @@ variables:
              python3-requests
              python3-tqdm
              python3-yaml
-  IMAGE: pureos/byzantium
 
 .tags: &tags
   tags:
@@ -14,7 +13,6 @@ variables:
 build:deb:
   <<: *tags
   stage: build
-  image: $IMAGE
   before_script:
     - export DEBIAN_FRONTEND=noninteractive
     - apt-get -y update
@@ -30,7 +28,6 @@ build:deb:
 test:download:deb:
   <<: *tags
   stage: test
-  image: $IMAGE
   before_script:
     - export DEBIAN_FRONTEND=noninteractive
     - apt-get -y update
@@ -49,7 +46,6 @@ test:download:deb:
 test:download:pip:
   <<: *tags
   stage: test
-  image: $IMAGE
   before_script:
     - export DEBIAN_FRONTEND=noninteractive
     - apt-get -y update