Update the README_ar.md

[ssakkout]

An update to the README_ar.md

to fix the typos in the file and improve the syntax according to Arabic Grammer

Some of the Changes Made

1. Spelling

Wrong words	Corrections
غوججر	غوجر
ريسنيت	ريسنت
ارفاق	إرفاق
الصيفة	الصيغة

2. Fixing non Arabic punctuation | , | ، |

1. Adding missing spaces 2. Improving the syntax in the contributions section