According to Dewan Bahasa & Pustaka, dinamika is a spelling mistake. The correct spelling is dinamik.
Instead of "dinamik politik", the term which you need to understand is "perubahan dinamik". Perubahan mean change, dinamik is equivalent to dynamic in English. So the whole term mean "dynamic change".
An example of dynamic change of politics is Tun Dr Mahathir resigned as prime minister and eventually replaced by Tan Sri Muhyiddin.