Fix source version for test

odersky · odersky · commit a8b80877616e · 2021-02-05T10:16:13.000+01:00
diff --git a/tests/pos/i11311.scala b/tests/pos/i11311.scala
@@ -1,3 +1,4 @@
+import language.`3.1`
 object Test:
 
   def cat1(s1: String)(s2: String) = s1 + s2
