Move SPC provider fixture helper

internal/providers/spc/fixture_test.go

@@ -0,0 +1,17 @@
+package spc
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+func readTestFile(t *testing.T, name string) []byte {
+	t.Helper()
+	path := filepath.Join("testdata", name)
+	raw, err := os.ReadFile(path)
+	if err != nil {
+		t.Fatalf("read %s: %v", path, err)
+	}
+	return raw
+}