test: fix chewing_version test

Author: kanru

tests/test-config.c

@@ -767,7 +767,11 @@ void test_runtime_version()
 
     ok(version != NULL, "chewing_version returns a version string");
 
-    sprintf(buf, "%d.%d.%d-%s", major, minor, patch, extra);
+    sprintf(buf, "%d.%d.%d", major, minor, patch);
+    if (strlen(extra) != 0) {
+        strcat(buf, "-");
+        strcat(buf, extra);
+    }
     ok(strcmp(buf, version) == 0, "chewing_version can be created from components");
 }