Polish doc

Closes gh-1843

Author: izeye

src/docs/asciidoc/core/core-databuffer-codec.adoc

@@ -46,7 +46,7 @@ In general, the following invariant holds for the read position, write position,
 [literal]
 [subs="verbatim,quotes"]
 --
-	`0` <= _read position_ <= _write position_ <= _capacity_
+	0 <= read position <= write position <= capacity
 --
 
 When reading bytes from the `DataBuffer`, the read position is automatically updated in accordance with