To modify the way IntelliJ deals with auto imports you need
to open the Settings dialog (𝗖𝘁𝗿𝗹+𝗔𝗹𝘁+𝗦)
and navigate to the 𝗘𝗱𝗶𝘁𝗼𝗿 | 𝗖𝗼𝗱𝗲 𝗦𝘁𝘆𝗹𝗲 | 𝗝𝗮𝘃𝗮 | 𝗜𝗺𝗽𝗼𝗿𝘁𝘀 𝘁𝗮𝗯.
In this dialog, you need to check the Use single class import option.
You'll also need to change the default limit for
𝗖𝗹𝗮𝘀𝘀 𝗰𝗼𝘂𝗻𝘁 𝘁𝗼 𝘂𝘀𝗲 𝗶𝗺𝗽𝗼𝗿𝘁 𝘄𝗶𝘁𝗵 '*'
𝗡𝗮𝗺𝗲𝘀 𝗰𝗼𝘂𝗻𝘁 𝘁𝗼 𝘂𝘀𝗲 𝘀𝘁𝗮𝘁𝗶𝗰 𝗶𝗺𝗽𝗼𝗿𝘁 𝘄𝗶𝘁𝗵 '*'
from 5 to a big enough threshold such as 999.