program::message::AccountKeys: `Clone`, `Default`, `Debug`, `Eq` (#33749)

It is a pretty standard set of traits to implement on most types.  Both `Pubkey`
and `LoadedAddresses` contained within the `AccountKeys` already implement them.
Doing the same for `AccountKeys` could simplify unit tests and/or some common
value manipulation logic.

sdk/program/src/message/account_keys.rs

@@ -4,11 +4,12 @@ use {
         message::{v0::LoadedAddresses, CompileError},
         pubkey::Pubkey,
     },
-    std::{collections::BTreeMap, ops::Index},
+    std::{collections::BTreeMap, iter::zip, ops::Index},
 };
 
 /// Collection of static and dynamically loaded keys used to load accounts
 /// during transaction processing.
+#[derive(Clone, Default, Debug, Eq)]
 pub struct AccountKeys<'a> {
     static_keys: &'a [Pubkey],
     dynamic_keys: Option<&'a LoadedAddresses>,
@@ -138,6 +139,12 @@ impl<'a> AccountKeys<'a> {
     }
 }
 
+impl PartialEq for AccountKeys<'_> {
+    fn eq(&self, other: &Self) -> bool {
+        zip(self.iter(), other.iter()).all(|(a, b)| a == b)
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use {super::*, crate::instruction::AccountMeta};