Don't document 1.18.4 compatibility with OTP28 (#14663)

Author: sabiwara

lib/elixir/pages/references/compatibility-and-deprecations.md

@@ -51,7 +51,7 @@ Elixir version | Supported Erlang/OTP versions
 :------------- | :-------------------------------
 1.20           | 26 - 28
 1.19           | 26 - 28
-1.18           | 25 - 27 (and Erlang/OTP 28 from v1.18.4)
+1.18           | 25 - 27
 1.17           | 25 - 27
 1.16           | 24 - 26
 1.15           | 24 - 26