amber/byzantium-jobs: Update the arm64 image name

`pureos/amber` and `pureos/byzantium` images now have a manifest
that allows the right image to be selected based on host architecture
automatically.
13 jobs for arm in 3 minutes and 31 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Test
passed #332386
librem5
test:native

00:00:13

 
  Package
passed #332390
librem5
package-debian-bullseye

00:01:04

passed #332388
librem5
package-debian-buster

00:01:06

failed #332387
librem5
package-pureos-amber

00:00:07

passed #332389
librem5
package-pureos-byzantium

00:01:01

 
  Test Package
passed #332397
librem5
autopkgtest-debian-bullseye-package

00:00:49

passed #332393
librem5
autopkgtest-debian-buster-package

00:00:39

skipped #332391
librem5
autopkgtest-pureos-amber-package
passed #332395
librem5
autopkgtest-pureos-byzantium-package

00:00:31

passed #332398
librem5
lintian-debian-bullseye-package

00:00:45

passed #332394
librem5
lintian-debian-buster-package

00:00:40

skipped #332392
librem5
lintian-pureos-amber-package
passed #332396
librem5
lintian-pureos-byzantium-package

00:00:44

 
Name Stage Failure
failed
package-pureos-amber Package
Err:3 http://repo.pureos.net/pureos amber-proposed-updates InRelease
The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 2B4A53F2B41CE072
Reading package lists...
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://repo.pureos.net/pureos amber InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 2B4A53F2B41CE072
W: GPG error: http://repo.pureos.net/pureos amber-phone-staging InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 2B4A53F2B41CE072
E: The repository 'http://repo.pureos.net/pureos amber-phone-staging InRelease' is not signed.
W: GPG error: http://repo.pureos.net/pureos amber-proposed-updates InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 2B4A53F2B41CE072
E: The repository 'http://repo.pureos.net/pureos amber-proposed-updates InRelease' is not signed.
ERROR: Job failed: exit code 1