CI: Install locales-all package

The test_gettext* files need specific locales available to exercise
their tests.

related: #15591

Signed-off-by: James McCoy <jamessan@jamessan.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index edad08a..905eb49 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -105,6 +105,7 @@
             libtool-bin \
             libncurses-dev:${{ matrix.architecture }} \
             libxt-dev:${{ matrix.architecture }} \
+            locales-all \
           )
           if ${{ matrix.features == 'huge' }}; then
             LUA_VER=${{ matrix.lua_ver || '5.4' }}