tests: fix data race in bad-block-report disabling during tests

tests/init.go

@@ -56,13 +56,16 @@ var (
 	VmSkipTests    = []string{}
 )
 
+// Disable reporting bad blocks for the tests
+func init() {
+	core.DisableBadBlockReporting = true
+}
+
 func readJson(reader io.Reader, value interface{}) error {
 	data, err := ioutil.ReadAll(reader)
 	if err != nil {
 		return fmt.Errorf("Error reading JSON file", err.Error())
 	}
-
-	core.DisableBadBlockReporting = true
 	if err = json.Unmarshal(data, &value); err != nil {
 		if syntaxerr, ok := err.(*json.SyntaxError); ok {
 			line := findLine(data, syntaxerr.Offset)