Enhance : Geom filter condition & Task limit

[kshitijrajsharma]

What does this PR do ?

• Introduces task limits on config
• Adds st_union function for the geom to handle situation like following . It will first make sure geom is valid and then perform union on the geom and applies buffer with tolerance 0.005 , which is negligible ( mainly to make sure we are not dealing with too many points and it will make postgres search query faster )

Consideration :

This could have been done with shapely , geopandas or any other geospatial libraries , since we are doing query directly on postgis , I preferred doing it in database level which will benefit us computation wise. Convex hull is also a good option within postgis but convex hull try to produce enclosing polygon , for our usecase union turns out ideal cause it can omit unnecessary parts specially if polygon is curve or C shaped thats why I opted for ST_UNION

Above input on query will result like following after geometrycheck , union and buffer