Vegetation Index values (equation) as string instead of List in jsonb

[marujore]

Vegetation Index values (equation) are being created as List instead of string in metadata jsonb.
Current:
{"expression": {"bands": [1218, 1213], "value": ["10000. * ((B8A - B04) / (B8A + B04))"]}}
Desidered
{"expression": {"bands": [1218, 1213], "value": "10000. * ((B8A - B04) / (B8A + B04))"}}