Bump docs for 3.2.0-RC2

To include another changelog entry: https://github.com/apache/couchdb-documentation/commit/4f00da0b0cedf63ebf391e43b1a56bb36f7d0f96
diff --git a/rebar.config.script b/rebar.config.script
index 25fd071..37b4852 100644
--- a/rebar.config.script
+++ b/rebar.config.script
@@ -154,7 +154,7 @@
 
 %% Non-Erlang deps
 {docs,             {url, "https://github.com/apache/couchdb-documentation"},
-                   {tag, "3.2.0-RC1"}, [raw]},
+                   {tag, "3.2.0-RC2"}, [raw]},
 {fauxton,          {url, "https://github.com/apache/couchdb-fauxton"},
                    {tag, "v1.2.7"}, [raw]},
 %% Third party deps