Benchmarks: Build Pipeline - Degrade perftest submodule to fix stability issue (#386)

**Description**
Degrade perftest submodule to v4.4-0.37 to fix stability issue.

Issue: rdma-loopback is not stable on public version(v0.5/v0.6-rc1)
Docker Version: v0.6-rc1-cuda11.1
Testbed: 8 A100 40GB GPUs (1 NDv4 node)
Result: 
New perftest version introduce the variance, max-min/mean = 2% for v4.4-0.37, 8% for v4.5-0.2

perftest @ 5fb4f10a

-Subproject commit 7504ce48ac396a02f4d00de359257b2cb8458f06
+Subproject commit 5fb4f10a7e7827ed15e53c25810a10be279d6e23