Rollup merge of rust-lang#62728 - DutchGhost:fix-double-wording, r=jonas-schievink

Fix repeated wording in slice documentation

Changes `of the slice of the slice` to `of the slice` in the chunk- and friends documentation of slices

Author: Mark-Simulacrum

src/libcore/slice/mod.rs

@@ -611,7 +611,7 @@ impl<T> [T] {
     ///
     /// See [`chunks_exact`] for a variant of this iterator that returns chunks of always exactly
     /// `chunk_size` elements, and [`rchunks`] for the same iterator but starting at the end of the
-    /// slice of the slice.
+    /// slice.
     ///
     /// # Panics
     ///
@@ -645,7 +645,7 @@ impl<T> [T] {
     ///
     /// See [`chunks_exact_mut`] for a variant of this iterator that returns chunks of always
     /// exactly `chunk_size` elements, and [`rchunks_mut`] for the same iterator but starting at
-    /// the end of the slice of the slice.
+    /// the end of the slice.
     ///
     /// # Panics
     ///
@@ -727,7 +727,7 @@ impl<T> [T] {
     ///
     /// See [`chunks_mut`] for a variant of this iterator that also returns the remainder as a
     /// smaller chunk, and [`rchunks_exact_mut`] for the same iterator but starting at the end of
-    /// the slice of the slice.
+    /// the slice.
     ///
     /// # Panics
     ///