I seem to revisit this more often than I really feel comfortable with since the first post back in 2014, but there are just so many times when I cannot perform a restart and still need to make changes.
So if you cannot wait for a change window, or you find yourself in a pinch you can use this technique to bypass the "Restart Computer" check on SQL installations.
1. Mount the SQL server ISO
2. Open Command prompt and navigate to your SQL Server media.
3. Then you will run a command that looks something like this:
Setup.exe /ACTION=Install /SkipRules=RebootRequiredCheck
You will now be prompted with the normal SQL installation wizard and can carry on as normal. When you get to the Support Rules check, the Restart Computer will be skipped.
Of course, this will likely cause you to be in a potentially unsupported state until you actually action the restart.
For those of you who need more information on using Command Prompt for SQL installs.