Compatibility fixes for new versions of PHPStan and Nette

[MartinMystikJonas]

I made some fixes for compatibility with new PHPStan and Nette,

There is still one error remaining for variables with default values I cannot solve. I am not sure if it is our unintended Latte behaviour. I recall @dg planned some changes to how {default} works.

Variable with defaut value:

{default $someVariableWithDefault = 'default value'}

is now transformed to:

$someVariableWithDefault ??= \array_key_exists('someVariableWithDefault', \get_defined_vars()) ? \null : 'default value';

So variable type is resolved to 'default value'|null instead of 'default value' as it was earlier.

We shuld also bump minimal PHPStan version for compatibility with new release.

[MartinMystikJonas]

Discussed here: https://forum.nette.org/cs/36681-zmena-chovani-default-v-latte-sjednoceni-s-operatorem#p227893

[lulco]

@MartinMystikJonas zda sa ze toho dost vela popadalo v testoch. Budes to fixovat?

[MartinMystikJonas]

Popadalo to v tagu {default}, protže Latte změnilo jak je implementovnaý a ta nová syntaxe je pro PHP stan neznámá

[MartinMystikJonas]

Tests should be fixed once this is merged to PHPStan: phpstan/phpstan-src#3624

[lulco]

Ok keď sa to mergne do phpstanu, a prejdú nám testy, môžeš mergovat

[spaze]

phpstan/phpstan-src#3624 has been merged and released in PHPStan 1.12.13/2.0.4. Can you try to rerun the tests to see if this PR can be merged?