Add PHP CS Fixer

[vjik]

Q	A
Is bugfix?	❌
New feature?	❌
Breaks BC?	❌

[codecov]

Codecov Report

❌ Patch coverage is 98.24561% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 98.12%. Comparing base (a7896f8) to head (e5c491e).
⚠️ Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
src/Builder/InBuilder.php	50.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff            @@
##             master     #375   +/-   ##
=========================================
  Coverage     98.12%   98.12%           
  Complexity      240      240           
=========================================
  Files            26       26           
  Lines           798      799    +1     
=========================================
+ Hits            783      784    +1     
  Misses           15       15           

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