Docker: set LANG=C.UTF-8

This prevents warning spam from Qt 6's rcc tool.

Author: slipher

Dockerfile

@@ -1,5 +1,9 @@
 # See Dockerfile.win for an explanation of some aspects of this file.
 FROM docker.io/debian:bullseye-slim
+
+# Prevents warning spam from Qt 6's rcc
+ENV LANG=C.UTF-8
+
 # OpenSSL build requires perl
 # Qt tarball requires xz-utils
 # Qt build requires libgl1-mesa-dev, libxkbcommon-dev, python, zlib1g-dev

Dockerfile.win

@@ -11,6 +11,10 @@
 # is stored in the updater/.git/modules directory.
 
 FROM docker.io/debian:bullseye-slim
+
+# Prevents warning spam from Qt 6's rcc
+ENV LANG=C.UTF-8
+
 RUN apt-get update && apt-get install -y \
     autoconf \
     autopoint \