flight data ingester demo

[dedlockdave]

This pull request adds the new directory to demonstrate greptimedbs ability to ingest flight data in particular geo spatial relationships such as:

• Longitude
• Latitude
• Velocity
• BaroAltitude
• GeoAltitude

To further develop this demo's usefulness we can add

• Grafana dashboard
• Metrics to understand what the value of x is during a timeframe at a specific location (s2 cell, h3 index or a polygon).

[sunng87]

Looks great to me. I made a minor modification to allow user using environment variable to customize airport.

[sunng87]

I'm going to merge this and let's focus on visualization.