The correct form of the verb "يرتضيه" when the answer of the conditional sentence is connected with the indicative mood (الفاء) is "يرضى".
Therefore, the correct sentence is:
من يرضى الهوان لنفسه يرضى لسواه
This means "Whoever accepts humiliation for himself will accept it for others."
The verb "يرتضيه" is in the subjunctive mood (الاستثناء) and is used when the answer of the conditional sentence is connected with the imperative mood (الأمر). For example:
من يرتضِ الهوان لنفسه فليتحمل عواقبه
This means "Whoever accepts humiliation for himself should bear its consequences."
In this case, the imperative verb "فليتحمل" is used to express a command or an obligation.
I hope this helps!