Fix warnings and compile errors on nightly (#6886)

Nightly has added a bunch of compiler and linter warnings. There is also
two dependencies that fail compilation on latest nightly due to using
the old `stdsimd` feature name. This PR fixes them.

libs/pageserver_api/src/models.rs

@@ -14,7 +14,6 @@ use byteorder::{BigEndian, ReadBytesExt};
 use postgres_ffi::BLCKSZ;
 use serde::{Deserialize, Serialize};
 use serde_with::serde_as;
-use strum_macros;
 use utils::{
     completion,
     history_buffer::HistoryBufferWithDropCounter,
@@ -1077,7 +1076,6 @@ impl PagestreamBeMessage {
 
 #[cfg(test)]
 mod tests {
-    use bytes::Buf;
     use serde_json::json;
 
     use super::*;

libs/pageserver_api/src/shard.rs

@@ -6,7 +6,6 @@ use crate::{
 };
 use hex::FromHex;
 use serde::{Deserialize, Serialize};
-use thiserror;
 use utils::id::TenantId;
 
 #[derive(Ord, PartialOrd, Eq, PartialEq, Clone, Copy, Serialize, Deserialize, Debug, Hash)]
@@ -656,10 +655,7 @@ fn key_to_shard_number(count: ShardCount, stripe_size: ShardStripeSize, key: &Ke
 
 #[cfg(test)]
 mod tests {
-    use std::str::FromStr;
-
-    use bincode;
-    use utils::{id::TenantId, Hex};
+    use utils::Hex;
 
     use super::*;