Description:
------------
On Windows PHP emits a warning if file path consists of existing file and slash plus optionally anything is appended. This issue should be fixes asap as it outputs unwanted output from core function.

Test script:
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(Windows + PHP 7.3 + PHP error reporting enabled + open_basedir set)

var_dump(file_exists(__FILE__));
var_dump(file_exists(__FILE__ . '/'));

Expected result:
----------------
bool(true)
(no warning)
bool(false)

Actual result:
--------------
bool(true)
Warning: file_exists(): open_basedir restriction in effect. File(C:/x/test.php/) is not within the allowed path(s): (C:/x/) in xxx on line xxx
bool(false)