Add rustfmt.toml and cargo fmt (#23238)

* fmt

* formatted

Co-authored-by: Lucas B <buffalu@jito.network>

sdk/program/src/slot_hashes.rs

@@ -2,13 +2,12 @@
 //!
 //! this account carries the Bank's most recent bank hashes for some N parents
 //!
+pub use crate::clock::Slot;
 use {
     crate::hash::Hash,
     std::{iter::FromIterator, ops::Deref},
 };
 
-pub use crate::clock::Slot;
-
 pub const MAX_ENTRIES: usize = 512; // about 2.5 minutes to get your vote in
 
 // This is to allow tests with custom slot hash expiry to avoid having to generate