feat: merge action log queries and add subscription for instructor comments

### Additions

* added new type `ActionLogsFilterType`
* added new input type `ActionLogsFilterInput`
* added new subscription `instructorComments(teamIds: [ID!]!): (log: ActionLogInterface!, event_type: EventType!)`

### Changes

* changed query `teamActionLogs(teamIds: [ID!]!, typeBlacklist: [LogType!] = [], exerciseId: ID)` to `teamActionLogs(logFilter: ActionLogsFilterInput!)`

### Deletions

* removed `teamChannelLogs` query, use `teamActionLogs` with the appropriate arguments
* removed `analyticsActionLogs` query, use `teamActionLogs` with the appropriate arguments

Closes #476