refactor: deprecate specifying timeAfter via taskOptions

[klesh]

Summary

In the current implementation, one can specify the timeAfter via the taskOptions like the following:

[
  [
    {"plugin": "github", "options": { "timeAfter": "2024-04-15T15:29:43Z", ... }},
    {"plugin": "jira", "options": { "timeAfter": "2023-04-15T15:29:43Z", ... }}
  ]
]

This looks flexible but doesn't make too much sense because a Project/Blueprint/Pipeline crunches the SAME time range of data from different data sources in most cases if not all.

So, this feature is rarely used because we have timeAfter on the Project/Blueprint/Pipeline level, it is easier to use.

For those who really need to collector different data sources with different time range can could use multiple Projects/Blueprints, or Pipelines. So no point in maintaining such a feature.

This PR remove the timeAfter option from the taskOptions for all plugin to simply our logic and make contributors life easier.