Improve installation instructions in alpine_install

alpine_install

@@ -1,7 +1,7 @@
 # Alpine Linux installation answers
 # Doc: https://docs.alpinelinux.org/user-handbook/0.1a/Installing/setup_alpine.html#_answer_files
 # Serve e.g. with "ncat -e '/bin/cat alpine_install' -l -p 2222 -k"
-# Get in alpine e.g. using "sleep 1 | nc … > file" and use with "setup-alpine -e -f file"
+# Get in alpine e.g. using "sleep 1 | nc … > file" and use with "yes | setup-alpine -e -f file"
 # After installation, boot the VM from the disk and run alpine_postinst script
 #     (serve similarly to this file). This script performs a few tweaks to the
 #     installation, like installing BIRD.