[BUG] Missing data point in DeepDrills when we have missing data

[Amatullah]

Describe the bug

DeepDrills calculates the end date wrong when the timeseries has a missing data point for the end date

Explain the environment

• Chaos Genius version: 0.1.2-alpha
• OS Version / Instance: AWS EC2
• Deployment type: Docker

Current behavior

Currently end_date is calculated as n-2, if the (n-2)^nd data point is missing then end_date = n-3. Deepdrills skips the (n-3)^rd data point and makes end_date as the (n-4)^th data point.

Screenshots

The end date here should be Nov 14th, but Nov14th we have no data, hence end date should be Nov 13th. As we can see from the grpah end date here is Nov 12th.