Add a sleep to guarantee task execution order which guarantees event … #1059

Job	Run time
linux-compat (manylinux1-x64)	9m 31s
linux-compat (manylinux1-x86)	9m 50s
linux-compat (manylinux2014-x64)	10m 1s
linux-compat (manylinux2014-x86)	9m 49s
linux-compat (al2-x64)	10m 40s
linux-compat (fedora-34-x64)	10m 40s
clang-sanitizers (,thread)	11m 47s
linux-compat (opensuse-leap)	10m 50s
clang-sanitizers (,address,undefined)	10m 56s
linux-compat (rhel8-x64)	10m 20s
linux-compiler-compat (clang-3)	10m 12s
linux-shared-libs	9m 54s
linux-compiler-compat (clang-6)	10m 19s
linux-compiler-compat (clang-8)	10m 54s
linux-compiler-compat (clang-9)	10m 42s
linux-compiler-compat (clang-10)	10m 39s
windows	11m 27s
linux-compiler-compat (clang-11)	11m 43s
linux-compiler-compat (gcc-4.8)	9m 35s
linux-compiler-compat (gcc-5)	10m 16s
linux-compiler-compat (gcc-6)	10m 4s
windows-app-verifier	13m 5s
linux-compiler-compat (gcc-7)	10m 0s
linux-compiler-compat (gcc-8)	10m 24s
windows-vc14 (x86)	10m 48s
osx	10m 26s
downstream	10m 51s
windows-vc14 (x64)	15m 9s
windows-shared-libs	10m 55s
	5h 11m 47s

Provide feedback