[Fix] Implement legacy PFASConfidence object construction (#404)

Co-authored-by: Tim Lorsbach <tim@lorsba.ch>
Reviewed-on: enviPath/enviPy#404

utilities/legacy.py

@@ -125,6 +125,7 @@ from envipy_additional_information.parsers import (
     LiquidMatrixSourceParser,
     OxygenUptakeRateParser,
     InitiatingOrganismParser,
+    PFASConfidenceParser,
 )
 
 logger = logging.getLogger(__name__)
@@ -673,7 +674,8 @@ def build_additional_information_from_request(request, type_):
         elif type_ == "studywst":
             # study_wst_cond = get_parameter(request, "studywstcond")
             raise ValueError("studywstcond is not yet implemented")
-
+        elif type_ == "pfasconfidence":
+            return PFASConfidenceParser.from_string(get_parameter(request, "level"))
         else:
             raise ValueError(f"No corresponding AdditionalInformation for {type_} found!")