chore: remove repeat words

Signed-off-by: cuishuang <imcusg@gmail.com>

library/core/src/hint.rs

@@ -189,7 +189,7 @@
 /// ```
 ///
 /// This example is quite unlike anything that would be used in the real world: it is redundant
-/// to put an an assertion right next to code that checks the same thing, and dereferencing a
+/// to put an assertion right next to code that checks the same thing, and dereferencing a
 /// pointer already has the builtin assumption that it is nonnull. However, it illustrates the
 /// kind of changes the optimizer can make even when the behavior is less obviously related.
 #[track_caller]

library/core/src/slice/sort/stable/drift.rs

@@ -200,7 +200,7 @@ fn logical_merge<T, F: FnMut(&T, &T) -> bool>(
     // If one or both of the runs are sorted do a physical merge, using
     // quicksort to sort the unsorted run if present. We also *need* to
     // physically merge if the combined runs would not fit in the scratch space
-    // anymore (as this would mean we are no longer able to to quicksort them).
+    // anymore (as this would mean we are no longer able to quicksort them).
     let len = v.len();
     let can_fit_in_scratch = len <= scratch.len();
     if !can_fit_in_scratch || left.sorted() || right.sorted() {