test(security): add poc for clipboard chunk accumulation (GHSA-jf7g-qghg-p54x)

[nbolton]

GHSA-jf7g-qghg-p54x

Master:

./cve_XXXX_XXXXX_clipboard_exhaustion.py
CVE-XXXX-XXXXX - unbounded clipboard chunk accumulation (GHSA-jf7g-qghg-p54x)
target: 127.0.0.1:24800  name: 'deskflow-poc'  transport: tls
declaring 1 byte(s), streaming 16 MiB (configured limit 3 MiB)
sampling rss of server pid 1495024

    streamed 16 MiB
  accepted: 16 MiB (16777216 bytes), peer alive after stream: True
  server rss: 70 -> 88 MiB (delta 18 MiB, threshold 8 MiB)
[FAIL] server retained the oversized buffer (rss grew 19009536 bytes) - VULNERABLE (GHSA-jf7g-qghg-p54x)

https://github.com/deskflow/deskflow-ghsa-jf7g-qghg-p54x/pull/1

./cve_XXXX_XXXXX_clipboard_exhaustion.py
CVE-XXXX-XXXXX - unbounded clipboard chunk accumulation (GHSA-jf7g-qghg-p54x)
target: 127.0.0.1:24800  name: 'deskflow-poc'  transport: tls
declaring 1 byte(s), streaming 16 MiB (configured limit 3 MiB)
sampling rss of server pid 1512557

    streamed 16 MiB
  accepted: 16 MiB (16777216 bytes), peer alive after stream: True
  server rss: 69 -> 72 MiB (delta 2 MiB, threshold 8 MiB)
[PASS] server rss stayed flat - oversized data discarded on receive