Move cleanup of queries to later in the shutdown sequence
to avoid TSAN report
WARNING: ThreadSanitizer: data race
Write of size 8 at 0x000000000001 by main thread:
#0 free <null>
#1 default_memfree lib/isc/mem.c:440
#2 mem_put lib/isc/mem.c:363
#3 isc__mem_free lib/isc/mem.c:1012
#4 main bin/tools/mdig.c:2231
Previous read of size 1 at 0x000000000005 by thread T1:
#0 dns_name_fromtext lib/dns/name.c:1121
#1 sendquery bin/tools/mdig.c:596
#2 sendqueries bin/tools/mdig.c:779
#3 dispatch lib/isc/task.c:1153
#4 run lib/isc/task.c:1345
#5 isc__trampoline_run lib/isc/trampoline.c:184
#6 <null> <null>
Thread T1 (running) created by main thread at:
#0 pthread_create <null>
#1 isc_thread_create pthreads/thread.c:79
#2 isc_taskmgr_create lib/isc/task.c:1435
#3 main bin/tools/mdig.c:2148
SUMMARY: ThreadSanitizer: data race in __interceptor_freeCloses #2533 (closed)