[Post-redesign] Y-axis scaling

**Problem**: For certain metrics like crash-free rates which are displayed as %, if all the values are within a small range (98% to 100%), the visualisation is not helpful since it appears as an almost stable line at the top.  **Proposed solution:** Add an auto-scale option in the widget builder (exact name TBD). When enabled, the minimum value of the Y-axis is also adjusted based on the min/max values within the time range. This should work similarly to the Project Details and Alerts charts for crash free sessions.