test: subprocessSetAPILevel: fix a linter warning

This fixes the following warning from gosimple linter:

> seccomp_test.go:146:2: S1021: should merge variable declaration with
> assignment on next line (gosimple)

Signed-off-by: Kir Kolyshkin <[email protected]>
Acked-by: Paul Moore <[email protected]>
Signed-off-by: Tom Hromatka <[email protected]>

Author: kolyshkin

seccomp_test.go

@@ -91,9 +91,8 @@ func TestSetAPILevel(t *testing.T) {
 	execInSubprocess(t, subprocessSetAPILevel)
 }
 func subprocessSetAPILevel(t *testing.T) {
-	var expectedAPI uint
+	const expectedAPI = uint(1)
 
-	expectedAPI = 1
 	err := SetAPI(expectedAPI)
 	if !APILevelIsSupported() {
 		if err == nil {