Fix documentation for (Partial)Guild::preferred_locale (#3413)

The `preferred_locale` field present on both `Guild` and `PartialGuild`
incorrectly states that it is only available for guilds with the `DISCOVERABLE`
feature.

This fixes the documentation to mention that it is actually available to
all guilds with the `COMMUNITY` feature.

Fixes #3363

Author: Nonanti

src/model/guild/mod.rs

@@ -188,7 +188,7 @@ pub struct Guild {
     pub premium_tier: PremiumTier,
     /// The total number of users currently boosting this server.
     pub premium_subscription_count: Option<u64>,
-    /// The preferred locale of this guild only set if guild has the "DISCOVERABLE" feature,
+    /// The preferred locale of this guild only set if guild has the "COMMUNITY" feature,
     /// defaults to en-US.
     pub preferred_locale: String,
     /// The id of the channel where admins and moderators of Community guilds receive notices from

src/model/guild/partial_guild.rs

@@ -147,7 +147,7 @@ pub struct PartialGuild {
     pub premium_tier: PremiumTier,
     /// The total number of users currently boosting this server.
     pub premium_subscription_count: Option<u64>,
-    /// The preferred locale of this guild only set if guild has the "DISCOVERABLE" feature,
+    /// The preferred locale of this guild only set if guild has the "COMMUNITY" feature,
     /// defaults to en-US.
     pub preferred_locale: String,
     /// The id of the channel where admins and moderators of Community guilds receive notices from