Fix: Remove query input in Vulnerabilities as not used and no API to support it

[ivanahuckova]

While investigating #304 I noticed that:

1. Query created in query field is not used in executed graphQL query to Github
2. The vulnerabilityAlerts query that we are creating doesn't support query parameter (for example some apis support it - such as milestones or labels) https://docs.github.com/en/graphql/reference/objects. So even if we wanted to implement it, github would need to support it first. Also I have checked securityVulnerabilities query type, but it wasn't providing query param in any of these (also I am not sure if securityVulnerabilities and vulnerabilityAlerts are the same thing, but both don't have query so I didn't look further). And lastly I've checked serach, but it does not have vulnerabilities type.

I have checked github reqests/questions on community site and it seems that there is none related to adding query param. So it would be worth to probably start there, but I'll leave this for users requesting this feature to ask there.

So this PR removes query input and logic as it isn't used anywhere.

Fixes #304

[zoltanbedi]

LGTM