Fix syntax errors in en/file-system/README.md

[mmunin]

Hi @sumn2u, all issues in the German (de) version have been fixed. Please check:

Original Comment	Issue	Correction
non blokcing i/0	Typo	non-blocking I/O
thats why runs at last as ti takes moer time	Grammar	that's why this runs last, as it takes more time
writting	Spelling	writing
intetntionally	Typo	intentionally
intentionally process is blocked	Grammar	the process is intentionally blocked
Callback in writeFileSync	Technical mistake	Remove the callback function

Looking forward to your review.
Best, @mmunin

[mmunin]

Hi @sumn2u, the errors are still in English; the German file has been newly created.
Should the English version really stay as it is?

[sumn2u]

Hi @sumn2u, the errors are still in English; the German file has been newly created. Should the English version really stay as it is?

I will be working on the fixes. Thanks for the reminder.