Hang up when receiver's CUDTUnited is being destroyed (Windows)

[maxsharabayko]

Reproduced with SRT v1.4.1 and later. Previous versions were not checked.
srt-xtransmit master Jan 28, 2020 939416e

Receiver:

srt-xtransmit.exe receive srt://:4200 -v --statsfreq 100ms --statsfile rcv-stats.csv

Sender:

srt-xtransmit.exe generate "srt://127.0.0.1:4200" --sendrate 1Mbps --duration 10s -v

When stats on the receiver are disabled, the isuue is not reproduced.
Receiver:

srt-xtransmit.exe receive srt://:4200 -v --statsfreq 100ms --statsfile rcv-stats.csv