Passenger crashes and leaves a core dump

[icarito]

This is related to #1191, the reason why unstable is failing to build, is because starting the app crashes passenger at some point and leaves a "core" file.

Since our binaries don't have debugging symbols, GDB is unable to give us much more information, it says:

icarito@tycho:/srv/mapknitter_unstable/mapknitter$ sudo gdb --core=core       
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[New LWP 8970]                                                                
Core was generated by `Passenger AppPreloader: /app (forking...)              
                     '.                                                       
Program terminated with signal SIGABRT, Aborted.                              
#0  0x00007fef54010fff in ?? ()                                               

Although the app seems to be able to run fine afterwards, the created dump file is unreadable by the Docker daemon so therefore next time we build the unstable staging instance, it fails to build.

I will disable creation of dump files in docker-compose configuration, but we should keep an eye into exactly what is crashing and how we can fix it.

I found an issue suggesting this is likely a problem with our version of Ruby so we may want to try to either upgrade or downgrade it and see if it goes away - mastodon/mastodon#6734