buildserver: set quiet options to stop apt-get spamming build logs

https://gitlab.com/fdroid/fdroidserver/issues/636#note_266483988

buildserver/provision-apt-get-install

@@ -5,7 +5,7 @@ set -e
 set -x
 
 debian_mirror=$1
-export DEBIAN_FRONTEND=noninteractive 
+export DEBIAN_FRONTEND=noninteractive
 
 printf 'APT::Install-Recommends "0";\nAPT::Install-Suggests "0";\n' \
        > /etc/apt/apt.conf.d/99no-install-recommends
@@ -22,6 +22,11 @@ EOF
 printf 'APT::Get::Assume-Yes "true";\n' \
        > /etc/apt/apt.conf.d/99assumeyes
 
+cat <<EOF > /etc/apt/apt.conf.d/99quiet
+Dpkg::Use-Pty "0";'
+quiet "1";'
+EOF
+
 if echo $debian_mirror | grep '^https' 2>&1 > /dev/null; then
     apt-get update || apt-get update
     apt-get install apt-transport-https ca-certificates