Regtest unique-id.vtc was added by commit 5fcec84c58 ("REGTEST: Add
unique-id reg-test") but it relies on the "uuid" sample fetch which
is only available in version 2.0 and above. Let's reflect that in
the REQUIRE_VERSION tag.
This reg-test verifies the following behavior:
1. That unique IDs are stable (i.e. the bug fixed in 530408f976e5fe2f2f2b4b733b39da36770b566f)
2. That unique IDs can use values from the HTTP request (see https://www.mail-archive.com/haproxy@formilux.org/msg36436.html)