Fix: used wrong variable for check.

Author: fangerer

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/common/SequenceStorageNodes.java

@@ -2724,7 +2724,7 @@ protected static boolean isFallbackCase(SequenceStorage s, Object value, IsAssig
             if (s instanceof EmptySequenceStorage || s instanceof ObjectSequenceStorage) {
                 return false;
             }
-            if ((value instanceof ByteSequenceStorage || value instanceof IntSequenceStorage || value instanceof LongSequenceStorage) &&
+            if ((s instanceof ByteSequenceStorage || s instanceof IntSequenceStorage || s instanceof LongSequenceStorage) &&
                             (value instanceof Byte || value instanceof Integer || value instanceof Long)) {
                 return false;
             }