[CS] Fix dynamic and broken indent detection, allow to configure spacing via RectorConfig::indent() method

[TomasVotruba]

Closes rectorphp/rector#7210

At the moment, the indent detection depens on every single space token in the code. If there is one tab, the code will be changed to tabs, which is non-sense.

When we look at the php-parser issue related to indentation, there is a possible way to configure the printer via options:
nikic/PHP-Parser#723 (comment)

Saying that, instead of magical indent guessing per file, we should let user configure the default space indent:

// 4 spaces
$rectorConfig->indent(' ', 4);

// one tab
$rectorConfig->indent("\t", 1);

Files must respect one indent way.

The rest code should be handled by CS tool like before: https://github.com/rectorphp/rector#how-to-apply-coding-standards

[samsonasik]

rules-tests seems error https://github.com/rectorphp/rector-src/runs/6752934495?check_suite_focus=true

[TomasVotruba]

I see. Few fixtures are using the tabs, let's update it

[TomasVotruba]

CI is passing 🎉