fix possible rector internal timeout when processing large apps

[LordSimal]

While doing another check if the current 6.0 rector rules properly apply on the core I noticed, that rector times out internally.

This fixes this issue. Unfortunately there is no global rector config for this present which can be applied across all ruleset (at least as far as I and my AI agent know)

@samsonasik thoughts?

Specifically I am talking about this error:

[ERROR] Could not process                                                      
         "/Users/kevin/Documents/CakePHP/Org/upgrade/vendor/rector/rector/vendor
         /symplify/easy-parallel/src/ValueObject/ParallelProcess.php" file, due 
         to:                                                                    
         "Child process timed out after 120 seconds". On line: 96               

 [ERROR] Could not process some files, due to:                                  
         "Reached system errors count limit of 50, exiting...".                 

Something went wrong while running rector.

This happened to me while using the 6.x of this branch and doing a

bin/cake upgrade rector --rules cakephp60 /Users/kevin/Documents/CakePHP/Org/cakephp/src

where /Users/kevin/Documents/CakePHP/Org/cakephp is on the current 5.x branch state.

Therefore I tried to apply all rules from the CakePHP 6.0 ruleset to the whole core framework at once

[samsonasik]

you can also reduce job size, eg:

    $rectorConfig->parallel(600, 32, 10);

job size is basically how many files that needs to be processed per worker.

ref documentation

https://getrector.com/documentation/troubleshooting-parallel#content-configure-parallel

[LordSimal]

In my case just increasing the timeout did the job, so I'd like to keep the default value here as you guys probably had reasons to choose those in the first place :D

[samsonasik]

you can import "global" config, eg:

$rectorConfig->import(__DIR__ . '/default-rector.php');

so you only change 1 default file if needed.