Prevent Debian packages from prompting for configuration.

At some point the Debian tzdata package started waiting for somebody to tell it
what timezone it was in, causing CI builds to timeout.

.cirrus.yml

@@ -3,7 +3,7 @@ linux-x86_64-binaries_task:
         image: ubuntu:latest
 
     setup_script:
-        - apt-get update && apt-get -y install build-essential libgtk2.0-dev libpulse-dev mesa-common-dev libgtksourceview2.0-dev libcairo2-dev libsdl2-dev libxv-dev libao-dev libopenal-dev libudev-dev zip
+        - apt-get update && DEBIAN_FRONTEND=noninteractive apt-get -y install build-essential libgtk2.0-dev libpulse-dev mesa-common-dev libgtksourceview2.0-dev libcairo2-dev libsdl2-dev libxv-dev libao-dev libopenal-dev libudev-dev zip
 
     compile_script:
         - make -C bsnes local=false
@@ -49,7 +49,7 @@ windows-x86_64-binaries_task:
         image: ubuntu:latest
 
     setup_script:
-        - apt-get update && apt-get -y install build-essential mingw-w64 zip
+        - apt-get update && DEBIAN_FRONTEND=noninteractive apt-get -y install build-essential mingw-w64 zip
 
     compile_script:
         - make -C bsnes local=false platform=windows compiler="x86_64-w64-mingw32-g++" windres="x86_64-w64-mingw32-windres"