_content/ref/mod: fix wording error

The text says "Go release version" but should say "Go version".

Fixes golang/go#62707.

Change-Id: I95f6f95088cd99fdadaa57d301083d484979cdb0
Reviewed-on: https://go-review.googlesource.com/c/website/+/530680
Reviewed-by: Bryan Mills <[email protected]>
Auto-Submit: Russ Cox <[email protected]>
LUCI-TryBot-Result: Go LUCI <[email protected]>

Author: rsc

Diff for: _content/ref/mod.md

@@ -534,7 +534,7 @@ major version. Individual minor and patch versions cannot be deprecated;
 ### `go` directive {#go-mod-file-go}
 
 A `go` directive indicates that a module was written assuming the semantics of a
-given version of Go. The version must be a valid [Go release version](/doc/toolchain#version),
+given version of Go. The version must be a valid [Go version](/doc/toolchain#version),
 such as `1.9`, `1.14`, or `1.21rc1`.
 
 The `go` directive sets the minimum version of Go required to use this module.