feat(common/models): extra Unicode-based wordbreaker unit tests

fix(common/models): reconnects unit tests for worker-internal submodules 🎡

auto: increment master version to 16.0.58

fix(android/engine): Fix Backspace key to delete without errant subkeys

auto: increment master version to 16.0.57

chore(linux): Fix ibus-keyman.postinst script

auto: increment master version to 16.0.56

chore(android): Reduce Toast notification noise

When installing ibus-keyman it could happen that we got an (ignored)
error "user name does not exist". This change tries to work around
this problem.

Co-authored-by: Marc Durdin <marc@durdin.net>

Co-authored-by: Marc Durdin <marc@durdin.net>

auto: increment master version to 16.0.55

chore(core): emcc off path for linux

fix(linux): Allow downgrades for installing build deps

chore(linux): Update debian changelog 🍒

chore: update core/ label

Merge pull request #7000 from keymanapp/chore/developer/keymanweb-compiler-remove-unused-dependencies

chore(developer): remove unused dependencies from KeymanWeb compiler 🛩

chore(core): rename json.hpp to jsonpp.hpp 🛩

auto: increment master version to 16.0.54

feat(linux): Dockerfile for linux builder

When install the keyman-build-deps_*.deb file it can happen that
we end up with a lower version number than what we previously
built. This change allows downgrades so that the build dependencies
can be installed.

(cherry picked from commit f2b12771)

- add Dockerfile in linux/Dockerfile, referencing linux/debian/control
- add docs in docs/build/linux-ubuntu.md

Fixes: #7102