doc/go1.22: fix stale id for math/rand/v2

For golang#61422.

Change-Id: If87f30229e5e5351e81d42c777259335af3533e6
Reviewed-on: https://go-review.googlesource.com/c/go/+/548878
Auto-Submit: Michael Pratt <[email protected]>
LUCI-TryBot-Result: Go LUCI <[email protected]>
Reviewed-by: Michael Knyszek <[email protected]>

Author: prattmic

doc/go1.22.html

@@ -240,7 +240,7 @@ <h2 id="bootstrap">Bootstrap</h2>
 
 <h2 id="library">Core library</h2>
 
-<h3 id="minor_library_changes">New math/rand/v2 package</h3>
+<h3 id="math_rand_v2">New math/rand/v2 package</h3>
 
 <p><!-- CL 502495 -->
   TODO: <a href="https://go.dev/cl/502495">https://go.dev/cl/502495</a>: math/rand/v2: start of new API; modified api/next/61716.txt