feat: add a note saying sync-chunk-writes is no-op (#600)

* Add a note saying `sync-chunk-writes` is noop

* condense into one sentence

* Update src/config/paper/server-properties.yml

Co-authored-by: Matouš Kučera <mk@kcra.me>

* clarify

* flag -> system property

---------

Co-authored-by: Matouš Kučera <mk@kcra.me>

Author: Toffikk

src/config/paper/server-properties.yml

@@ -225,7 +225,9 @@ spawn-protection:
     at least 1 operator to be enabled.
 sync-chunk-writes:
   default: "true"
-  description: "Enables synchronous writing of chunk data."
+  description: |
+    Enables synchronous writing of chunk data. Has no effect on Paper by default, unless the corresponding system property is also set to true.
+    See [the system properties reference](/paper/reference/system-properties#paperenable-sync-chunk-writes).
 text-filtering-config:
   default: ""
   description: "The path to the text filtering configuration file. Leave blank to disable text filtering."