Update module golang.org/x/sync to v0.12.0

| datasource | package           | from    | to      |
| ---------- | ----------------- | ------- | ------- |
| go         | golang.org/x/sync | v0.11.0 | v0.12.0 |


Signed-off-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

go.mod

@@ -1,5 +1,7 @@
 module github.com/nginx/nginx-plus-go-client/v2
 
-go 1.22.6
+go 1.23.0
 
-require golang.org/x/sync v0.11.0
+toolchain go1.24.1
+
+require golang.org/x/sync v0.12.0

go.sum

@@ -1,2 +1,2 @@
-golang.org/x/sync v0.11.0 h1:GGz8+XQP4FvTTrjZPzNKTMFtSXH80RAzG+5ghFPgK9w=
-golang.org/x/sync v0.11.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
+golang.org/x/sync v0.12.0 h1:MHc5BpPuC30uJk597Ri8TV3CNZcTLu6B6z4lJy+g6Jw=
+golang.org/x/sync v0.12.0/go.mod h1:1dzgHSNfp02xaA81J2MS99Qcpr2w7fw1gpm99rleRqA=