Add HACS link in readme

[tanishqmanuja]

[litinoveweedle]

Hello, thank you for the PR.

Does this link also work, if this repo is not registered in HACS? (i.e. it is custom repo and you need to add github URL manually)?

[tanishqmanuja]

Yeah, It works for me even without adding the repo to the custom repositories. You can click/open link and check to be double sure. If this is your first time clicking HA redirect adjust your home assistant url accordingly