detect/http: fix compile warning in body tests #9323

Job	Run time
Prepare cbindgen	23s
Prepare dependencies	56s
AlmaLinux 9 Test Templates	5m 14s
AlmaLinux 8	5m 37s
AlmaLinux 9	12m 41s
AlmaLinux 9 (no jansson)	1m 20s
Debian 10	7m 24s
Debian 11 (xdp)	7m 15s
Debian 12	23m 14s
Debian 12 Dist Builder	4m 20s
Debian 12 MSRV	22m 12s
Fedora 38 (clang, debug, asan, wshadow, rust-strict, systemd)	57m 10s
Fedora 38 (Suricata Verify codecov)	7m 43s
Fedora 38 (gcc, debug, asan, wshadow, rust-strict)	8m 30s
Fedora 39 (clang, debug, asan, wshadow, rust-strict, systemd)	8m 10s
Fedora 39 (gcc, debug, asan, wshadow, rust-strict)	8m 17s
Fedora 39 (non-root, debug, clang, asan, wshadow, rust-strict, systemd)	7m 22s
MacOS Latest	16m 41s
Ubuntu 20.04 (-DNDEBUG)	9m 19s
Ubuntu 22.04 (fuzz corpus coverage)	13m 34s
Ubuntu 22.04 (unittests coverage)	7m 1s
Ubuntu 22.04 (Debug Validation)	9m 40s
Ubuntu 22.04 (DPDK Build) (22.11.3)	14m 41s
Ubuntu 22.04 (Fuzz)	6m 16s
Ubuntu 22.04 (DPDK Build) (21.11.5)	12m 4s
Ubuntu 22.04 (DPDK Build) (20.11.9)	10m 38s
Ubuntu 22.04 (Netmap build)	3m 24s
Windows MSYS2 MINGW64 (libpcap)	25m 6s
Ubuntu 22.04 (DPDK Build) (19.11.14)	9m 12s
Windows MSYS2 MINGW64 (NPcap)	25m 44s
Windows MSYS2 MINGW64 (WinDivert)	12m 45s
CentOS Stream 8	5m 41s
CentOS 7	14m 46s
Ubuntu 20.04 (unsupported rust)	2m 10s
CentOS Stream 9	5m 32s
	6h 32m 2s

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