Change license for (some previous and) future revisions to GPL-3.0-or-later

From this revision on, all changes that were under the following
authors' names are also under GPL-3.0-or-later, and not just future
changes:
- Maxime Buquet (or Maxime “pep” Buquet)

Signed-off-by: Maxime “pep” Buquet <pep@bouah.net>
8 jobs for license-change in 3 minutes and 16 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Lint
passed #33433
mypy

00:01:43

failed #33431
pylint-latest

00:02:56

passed #33432
pylint-plugins

00:03:16

passed #33430
security-check

00:01:18

 
  Test
skipped #33437
pytest-3.10
skipped #33434
pytest-3.7
skipped #33435
pytest-3.8
skipped #33436
pytest-3.9
 
Name Stage Failure
failed
pylint-latest Lint
Finished processing dependencies for poezio==0.13.1.dev1328
$ pylint -E poezio
************* Module poezio.connection
poezio/connection.py:90:12: E1101: Instance of 'object' has no 'resource' member (no-member)
poezio/connection.py:249:12: E1101: Instance of 'Connection' has no 'handler' member (no-member)
************* Module poezio.core.core
poezio/core/core.py:569:26: E1101: Instance of 'object' has no 'split' member (no-member)
Cleaning up file based variables
ERROR: Job failed: exit code 1