Add test case for bug #46569

Author: cmb69

ext/spl/tests/bug46569.csv

@@ -0,0 +1,5 @@
+first,line
+second,line
+third,line
+fourth,line
+fifth,line

ext/spl/tests/bug46569.phpt

@@ -0,0 +1,14 @@
+--TEST--
+Bug #46569 (SplFileObject: fgetcsv after seek returns wrong line)
+--FILE--
+<?php
+$file = new SplFileObject(__DIR__ . '/bug46569.csv');
+$file->seek(1);
+print_r($file->fgetcsv());
+?>
+--EXPECT--
+Array
+(
+    [0] => second
+    [1] => line
+)