MetricsSerializer breaks for missing subindicator

In MetricsSerializer there is an error when the Subindicator is not available for a specific geography:

wazimap-ng/wazimap_ng/profile/serializers/metrics_serializer.py

Lines 31 to 35 in 06ce11f

    
           indicator_data = IndicatorData.objects.filter(indicator__profilekeymetrics=profile_key_metric, geography=geography) 
        
           if indicator_data.count() > 0: 
        
               subindicator = get_subindicator(profile_key_metric) 
        
               data = indicator_data.first().data # TODO what to do with multiple results 
        
               return data["subindicators"][subindicator]

If subindicator is not available this will result in a 500 server error. With KeyError

There are several things that need to happen here:

create a test for this edge case
use .get instead of []
return a default value if the subindicator is missing: N/A

https://trello.com/c/svbZLvHv/650-absolute-value-calculator-bug

	indicator_data = IndicatorData.objects.filter(indicator__profilekeymetrics=profile_key_metric, geography=geography)
	if indicator_data.count() > 0:
	subindicator = get_subindicator(profile_key_metric)
	data = indicator_data.first().data # TODO what to do with multiple results
	return data["subindicators"][subindicator]