wl_event_source_remove() is illegal after display has been destroyed,
so just destroy everything when we still can.
==20392==ERROR: AddressSanitizer: heap-use-after-free on address 0x607000001240 at pc 0x00000048e86e bp 0x7ffe4b557e00 sp 0x7ffe4b557df0
READ of size 8 at 0x607000001240 thread T0
#0 0x48e86d in wl_list_insert ../common/list.c:149
#1 0x7fdf673d4d7d in wl_event_source_remove src/event-loop.c:487
#2 0x41b742 in ipc_terminate ../sway/ipc-server.c:94
#3 0x40b1ad in main ../sway/main.c:440
#4 0x7fdf6664c18a in __libc_start_main ../csu/libc-start.c:308
#5 0x409359 in _start (/opt/wayland/bin/sway+0x409359)
0x607000001240 is located 48 bytes inside of 72-byte region [0x607000001210,0x607000001258)
freed by thread T0 here:
#0 0x7fdf692c4880 in __interceptor_free (/lib64/libasan.so.5+0xee880)
#1 0x7fdf673d371a in wl_display_destroy src/wayland-server.c:1097
previously allocated by thread T0 here:
#0 0x7fdf692c4c48 in malloc (/lib64/libasan.so.5+0xeec48)
#1 0x7fdf673d4d9e in wl_event_loop_create src/event-loop.c:522
#2 0x40acb2 in main ../sway/main.c:363
#3 0x7fdf6664c18a in __libc_start_main ../csu/libc-start.c:308
