docs/fuzz: fix outdated mention to enable-sanitizers

This options has been removed at cb771ac1f5 (meson: Split
--enable-sanitizers to --enable-{asan, ubsan}, 2024-08-13), so let's
update its last standing mention in the docs.

Signed-off-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Reviewed-by: Brian Cain <bcain@quicinc.com>
Message-ID: <0ecf4e1ab26771009d74a2ce61e7c17ddc586ef7.1726226316.git.quic_mathbern@quicinc.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
1 file changed