Use str, Enum instead of StrEnum (which is only compatible with py3.11+)

Author: softwareengineerprogrammer

src/geophires_x/Economics.py

@@ -1009,9 +1009,9 @@ def __init__(self, model: Model):
                                    for it in WellDrillingCostCorrelation]) +
                         f'. '
                         f'Baseline correlations (1-4) are from '
-                        f'{_WellDrillingCostCorrelationCitation.NREL_COST_CURVE_2025}.'
+                        f'{_WellDrillingCostCorrelationCitation.NREL_COST_CURVE_2025.value}.'
                         f' Intermediate and ideal correlations (6-17) are from '
-                        f'{_WellDrillingCostCorrelationCitation.GEOVISION}.'
+                        f'{_WellDrillingCostCorrelationCitation.GEOVISION.value}.'
 
         )
         self.DoAddOnCalculations = self.ParameterDict[self.DoAddOnCalculations.Name] = boolParameter(

src/geophires_x/OptionList.py

@@ -1,6 +1,6 @@
 # copyright, 2023, Malcolm I Ross
 
-from enum import Enum, StrEnum
+from enum import Enum
 
 
 class GeophiresInputEnum(str, Enum):
@@ -156,7 +156,7 @@ def from_input_string(input_string: str):
         raise ValueError(f'Unknown Reservoir Volume input value: {input_string}')
 
 
-class _WellDrillingCostCorrelationCitation(StrEnum):
+class _WellDrillingCostCorrelationCitation(str, Enum):
     """
     Values are abbreviated citations used in tooltip text.
     Commented full citations are present in CHANGELOG and could also be used in future documentation.