inets: Fix flaky tests in httpc_SUITE #13518

Job	Run time
Event File	3s
Build Erlang/OTP (64-bit)	7m 42s
Build Erlang/OTP (iOS)	6m 17s
Build Erlang/OTP (Windows)	14m 48s
Build Erlang/OTP (32-bit)	8m 33s
Build Erlang/OTP (macOS)	11m 33s
Build Erlang/OTP (cross-compile)	13m 35s
Build and check documentation	8m 25s
Build Erlang/OTP (clang)	5m 40s
Build Erlang/OTP (Types and Flavors)	0s
Run static analysis	6m 52s
Test Erlang/OTP (inets)	9m 47s
Release Erlang/OTP	0s
Test Erlang/OTP (system)	8m 36s
	1h 41m 51s

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