Require tls by default. (#1698)

prosody/rootfs/defaults/prosody.cfg.lua

@@ -1,4 +1,4 @@
-{{ $C2S_REQUIRE_ENCRYPTION := .Env.PROSODY_C2S_REQUIRE_ENCRYPTION | default "0" | toBool -}}
+{{ $C2S_REQUIRE_ENCRYPTION := .Env.PROSODY_C2S_REQUIRE_ENCRYPTION | default "1" | toBool -}}
 {{ $ENABLE_AUTH := .Env.ENABLE_AUTH | default "0" | toBool -}}
 {{ $ENABLE_GUEST_DOMAIN := and $ENABLE_AUTH (.Env.ENABLE_GUESTS | default "0" | toBool) -}}
 {{ $ENABLE_VISITORS := .Env.ENABLE_VISITORS | default "0" | toBool -}}