Fix warnings to unblock Clippy CI (#306)

1. Add `doc_nightly` to list of custom cfgs

2. Remove `#[cfg(...)]`s mentioning the `time` feature

The `time` crate, alongside its corresponding `time` feature, is no
longer used by poise anymore. Code that branches whether we're using
`chrono` or `time` can simply check just for `chrono`.

Cargo.toml

@@ -47,6 +47,9 @@ collector = []
 # build time for peace of mind.
 handle_panics = []
 
+[lints.rust]
+unexpected_cfgs = { level = "warn", check-cfg = ["cfg(doc_nightly)"] }
+
 [package.metadata.docs.rs]
 all-features = true
 rustdoc-args = ["--cfg", "doc_nightly"]

src/builtins/mod.rs

@@ -12,9 +12,9 @@ pub use pretty_help::*;
 mod register;
 pub use register::*;
 
-#[cfg(any(feature = "chrono", feature = "time"))]
+#[cfg(feature = "chrono")]
 mod paginate;
-#[cfg(any(feature = "chrono", feature = "time"))]
+#[cfg(feature = "chrono")]
 pub use paginate::*;
 
 use crate::{serenity::CreateAllowedMentions, serenity_prelude as serenity, CreateReply};

src/structs/context.rs

@@ -300,7 +300,7 @@ context_methods! {
     }
 
     /// Return a ID that uniquely identifies this command invocation.
-    #[cfg(any(feature = "chrono", feature = "time"))]
+    #[cfg(feature = "chrono")]
     (id self)
     (pub fn id(self) -> u64) {
         match self {
@@ -316,11 +316,6 @@ context_methods! {
 
                     // Calculate Discord's datetime representation (millis since Discord epoch) and
                     // insert those bits into the ID
-
-                    #[cfg(feature = "time")]
-                    let timestamp_millis = edited_timestamp.unix_timestamp_nanos() / 1_000_000;
-
-                    #[cfg(not(feature = "time"))]
                     let timestamp_millis = edited_timestamp.timestamp_millis();
 
                     id |= ((timestamp_millis - 1420070400000) as u64) << 22;