Revert "BinaryStream: add PHPStan type hint for get() parameter"

This reverts commit 22ac3f1.

This doc comment turned out to be very inconvenient and would require
propagating signed/unsigned types everywhere. Considering we're in the
process of phasing out this library anyway, it doesn't make much sense
to introduce this inconvenience everywhere.

src/BinaryStream.php

@@ -63,8 +63,6 @@ public function getBuffer() : string{
 	/**
 	 * @phpstan-impure
 	 * @throws BinaryDataException if there are not enough bytes left in the buffer
-	 *
-	 * @phpstan-param int<0, max> $len
 	 */
 	public function get(int $len) : string{
 		if($len === 0){