[gardening] Fix typos.

Author: practicalswift

stdlib/public/core/UnsafeRawBufferPointer.swift.gyb

@@ -65,7 +65,7 @@
 ///
 /// Example (continued):
 /// ```swift
-///   // Copy a another slice of memory back into the original slice.
+///   // Copy another slice of memory back into the original slice.
 ///   destBytes[0..<n] = someBytes[m..<(m+n)]
 /// ```
 ///

test/stdlib/UnsafeRawBufferPointer.swift

@@ -100,7 +100,7 @@ UnsafeRawBufferPointerTestSuite.test("empty") {
 }
 
 // Store a sequence of integers to raw memory, and reload them as structs.
-// Strore structs to raw memory, and reload them as integers.
+// Store structs to raw memory, and reload them as integers.
 UnsafeRawBufferPointerTestSuite.test("reinterpret") {
   struct Pair {
     var x: Int32