extract($arr, EXTR_SKIP) should not invalidate previous variables

[gharlan]

https://psalm.dev/r/35e85a72e3

When using the EXTR_SKIP flag for extract(), the existing variable types should not be invalidated by the extract call.

[psalm-github-bot]

I found these snippets:

https://psalm.dev/r/35e85a72e3

<?php

$a = 1;

extract([], EXTR_SKIP);

/** @psalm-trace $a */
$a;

Psalm output (using commit 206332b):

INFO: Trace - 8:1 - $a: mixed

[orklah]

It's handled here:

psalm/src/Psalm/Internal/Analyzer/Statements/Expression/Call/NamedFunctionCallHandler.php

Line 200 in 7c24d33

$mixed_type = Type::getMixed();

Currently, every variable in the scope except a few exception is turned into mixed