tests: compare a flag enum as an int in enum_method_duplicated_err

The fixture is about a method that duplicates a builtin method of an enum,
but that method's body compared a flag enum with an int literal,
`f & f2 > 0`, which V1 rejects too and which this check now reports,
before the error the fixture is about. The body casts to int, as V asks,
and the fixture shows its own error only.

Author: MARCROCK22

vlib/v/parser/tests/enum_method_duplicated_err.out

@@ -3,5 +3,5 @@ vlib/v/parser/tests/enum_method_duplicated_err.vv:13:14: error: duplicate method
    12 | 
    13 | fn (f Flags) has(f2 Flags) bool {
       |              ~~~
-   14 |     return f & f2 > 0
+   14 |     return int(f & f2) > 0
    15 | }

vlib/v/parser/tests/enum_method_duplicated_err.vv

@@ -11,7 +11,7 @@ enum Flags {
 }
 
 fn (f Flags) has(f2 Flags) bool {
-	return f & f2 > 0
+	return int(f & f2) > 0
 }
 
 fn main() {}