eval_pr: break autogame from ASan build to its own command line option

[jwrober]

Is your feature request related to a problem? Please describe.
Right now the ./scripts/eval_pr script that the admins use to automate the evaluation of pull requests has two compilation methods: Debug and ASan. The Debug method simply compiles, installs and run's cpack and stops. The ASan method compiles with the ASan preset and the automatically runs an autogame.

Describe the solution you'd like
ASan does not compile with Debug, but instead use RelWithDebInfo due to a collection of factors. When running an autogame, it is sometimes useful to run the server and client inside of a debugger (such as gdb) so if an assertion occurs or a segfault of some kind occurs a tester can get a backtrace to aid an issue later on.

What I would like is to have a separate function for calling an autogame in the script. The regular Debug and ASan presets can be used and then if you want the script to run an autogame, you can do that.

Describe alternatives you've considered
Could also simply remove the autostart of the autogame from ASan and simply echo out instructions on how to start one if a user wants to go that route.

Additional context
None