ci/cross-i386: pin Go to 1.21.x

Signed-off-by: Kir Kolyshkin <[email protected]>
Signed-off-by: Aleksa Sarai <[email protected]>

Author: kolyshkin

.github/workflows/test.yml

@@ -146,7 +146,7 @@ jobs:
     - name: install go
       uses: actions/setup-go@v5
       with:
-        go-version: 1.x # Latest stable
+        go-version: 1.21.x # TODO: switch to 1.x (latest stable) once Go 1.22 vs glibc issue is fixed.
 
     - name: unit test
       env: