Merge branch 'runtime_select_event_loop' of github.com:awslabs/aws-c-… #2861

Job	Run time
linux-byo-crypto	2m 41s
linux-compiler-compat (clang-3)	6m 21s
linux-compiler-compat (clang-6)	7m 13s
linux-shared-libs	2m 6s
downstream	43m 15s
linux-compiler-compat (clang-8)	10m 14s
linux-compat (manylinux1-x64)	6m 25s
clang-sanitizers (,thread)	6m 43s
linux-compiler-compat (clang-9)	9m 1s
windows	2m 47s
clang-sanitizers (,address,undefined)	7m 19s
linux-compiler-compat (clang-10)	6m 25s
linux-compat (manylinux1-x86)	6m 25s
linux-compat (manylinux2014-x64)	6m 6s
linux-debug	5m 54s
linux-compat (manylinux2014-x86)	6m 15s
linux-compiler-compat (clang-11)	7m 6s
linux-compiler-compat (gcc-4.8)	6m 37s
windows-vc14 (x86)	1m 25s
linux-compiler-compat (gcc-5)	6m 25s
windows-vc14 (x64)	1m 30s
linux-compiler-compat (gcc-6)	6m 49s
linux-compiler-compat (gcc-7)	6m 1s
linux-compat (fedora-34-x64)	6m 20s
linux-compiler-compat (gcc-8)	6m 0s
macos-debug (-DAWS_USE_APPLE_NETWORK_FRAMEWORK=ON)	1m 49s
windows-app-verifier	2m 29s
macos-debug (-DAWS_USE_APPLE_NETWORK_FRAMEWORK=OFF)	2m 18s
linux-compat (opensuse-leap)	7m 19s
windows-debug	3m 8s
linux-compat (rhel8-x64)	6m 39s
linux-compat (al2-x64)	6m 0s
windows-shared-libs	2m 35s
freebsd	6m 31s
macos (-DAWS_USE_APPLE_NETWORK_FRAMEWORK=ON)	1m 35s
macos (-DAWS_USE_APPLE_NETWORK_FRAMEWORK=OFF)	2m 24s
macos-x64	2m 37s
openbsd	10m 32s
	3h 59m 19s

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