Add soft-fail to hls buildkite step

[paolino]

Hls check is not reliable any more.

I.e checking out a commit like 6a7bfdf40d

git checkout 6a7bfdf

and

nix develop --command bash -c "haskell-language-server lib/wallet/src/Cardano/Wallet.hs"

it passes on my machine and @Unisay 's one but not on buildkite agent
I tried removing hie-bios cache and ghcide on the agents home and removing all clones

rm -rf ~/.cache/ghcide/
rm -rf ~/.cache/hie-bios/
find . -name cardano-wallet | xargs rm -rf

The problem persists

• Let HLS test soft-fail until after the release
• Added a high priority ticket https://cardanofoundation.atlassian.net/browse/ADP-3236