build: use the official action to download syft instead of implementi…

…ng it locally

this should mean that (besides version updates) we should not need to
touch this ever again, as when the install method changes the action
owners (who are the publishers of syft itself) will adjust their action.

build: continue to ship the old path inside the docker image

We pay a tax of doubling the image size, just to support the legacy
consumers, but this should be droppable with the next major version.

build: get closer to the original filenames we released so far

build: stick to the default GOOS and GOARCH based naming

fix(goreleaser): fix version to v2 and remove no longer supported flag

chore(release): v3.0.3

chore(release): v3.0.2

chore(release): v3.0.1

chore(release): v3.0.0

chore(release): 2.8.0