definitions: Lintian-ignore changed-by-invalid-for-derivative

The ci adds a changelog entry that doesn't match the current
requirements

  changed-by-invalid-for-derivative Librem5 CI <librem5-builds@lists.community.puri.sm> (should use @puri.sm email addresses)

but these look too tight anyway, see

    https://tracker.pureos.net/T1075

so lets keep the mailing list as go-to point and suppress the error for
now.
13 jobs for master in 3 minutes and 16 seconds (queued for 3 seconds)
Status Name Job ID Coverage
  Test
passed test:native #366436
librem5

00:00:14

 
  Package
passed package-debian-bullseye #366440
librem5

00:00:39

passed package-debian-buster #366438
librem5

00:00:39

passed package-pureos-amber #366437
librem5

00:00:39

passed package-pureos-byzantium #366439
librem5

00:00:41

 
  Test Package
passed autopkgtest-debian-bullseye-package #366447
librem5

00:00:31

passed autopkgtest-debian-buster-package #366443
librem5

00:00:29

passed autopkgtest-pureos-amber-package #366441
librem5

00:00:40

passed autopkgtest-pureos-byzantium-package #366445
librem5

00:00:54

passed lintian-debian-bullseye-package #366448
librem5

00:00:31

passed lintian-debian-buster-package #366444
librem5

00:00:35

passed lintian-pureos-amber-package #366442
librem5

00:00:37

passed lintian-pureos-byzantium-package #366446
librem5

00:00:46