Add support for multiple api keys

[elieobeid7]

Currently, the firestore extension supports multiple hosts with 1 API key, this isn't ideal

Add support for multiple API keys, either store multiple API keys in the secret manager or have them coma separated just like the host, you just have to ensure that there's no comma in the API key

I was trying to fix it but turns out the typesense js client only accepts one key!

[elieobeid7]

closing this issue as it turns out, this issue is caused by the javascript library itself.