_content/doc/go1.24: use en dash for number range

Change-Id: I85cb07e3930c3768ad53b201203711f1378c7a1b
Reviewed-on: https://go-review.googlesource.com/c/website/+/636075
Reviewed-by: Dmitri Shuralyov <[email protected]>
LUCI-TryBot-Result: Go LUCI <[email protected]>
Reviewed-by: Austin Clements <[email protected]>

Author: dominikh

_content/doc/go1.24.md

@@ -150,7 +150,7 @@ For protocol details, see [#59719](/issue/59719).
 <!-- go.dev/issue/68578 -->
 
 Several performance improvements to the runtime have decreased CPU overheads by
-2—3% on average across a suite of representative benchmarks.
+2–3% on average across a suite of representative benchmarks.
 Results may vary by application.
 These improvements include a new builtin `map` implementation based on
 [Swiss Tables](https://abseil.io/about/design/swisstables), more efficient