[Printer] Remove ltrim() on BetterStandardPrinter

[samsonasik]

first step to migrate to php-parser 5:

on php-parser 4, ltrim is added on print format preserving:

• https://github.com/nikic/PHP-Parser/blob/715f4d25e225bc47b293a8b997fe6ce99bf987d2/lib/PhpParser/PrettyPrinterAbstract.php#L503

on php-parser 5, ltrim is removed on print format preserving:

• https://github.com/nikic/PHP-Parser/blob/8eea230464783aa9671db8eea6f8c6ac5285794b/lib/PhpParser/PrettyPrinterAbstract.php#L581

as space before <?php is allowed on no-namespaced code.

so just use parent stmt method.

Next is to remove ltrim() on FileProcessor:

rector-src/src/Application/FileProcessor.php

Line 160 in 2c5cd97

$ltrimOriginalFileContent = ltrim($file->getOriginalFileContent());

when upgraded to php-parser 5.

part of rectorphp/rector#8815 process.

[samsonasik]

All checks have passed 🎉 @TomasVotruba ready to merge 👍

[TomasVotruba]

LGTM 👍