Support inline value sets in UP Sender Transform schema

- Require that the value FHIR expression evaluate prior to performing a valueset transform
- Change the valueset value to be parsed as a string rather than a FHIRPath expression
- Ensure the original untransformed value is preserved if a valueset key is not matched
- Added unit testing for valueset
- Reorganized unit tests and adjusted existing tests to match expected behavior
- ktLint formatting updates unrelated to this story

prime-router/src/main/kotlin/fhirengine/translation/hl7/ConfigSchemaProcessor.kt

@@ -6,6 +6,7 @@ import gov.cdc.prime.router.fhirengine.translation.hl7.utils.FhirPathUtils
 import org.apache.logging.log4j.kotlin.Logging
 import org.hl7.fhir.r4.model.Base
 import org.hl7.fhir.r4.model.Bundle
+import org.hl7.fhir.r4.model.StringType
 
 abstract class ConfigSchemaProcessor : Logging {
 
@@ -40,7 +41,7 @@ abstract class ConfigSchemaProcessor : Logging {
 
         // when valueSet is available, use the matching value else just pass the value as is
         // does a lowerCase comparison
-        if (element.valueSet.isNotEmpty()) {
+        if (retVal.isNotBlank() && element.valueSet.isNotEmpty()) {
             val lowerSet = element.valueSet.mapKeys { it.key.lowercase() }
             retVal = lowerSet.getOrDefault(retVal.lowercase(), retVal)
         }
@@ -71,15 +72,15 @@ abstract class ConfigSchemaProcessor : Logging {
             }
         }
 
-        // when valueSet is available, use the matching value else just pass the value as is
+        // when valueSet is available, return mapped value or null if match isn't found
         // does a lowerCase comparison
-        if (element.valueSet.isNotEmpty()) {
+        if (retVal != null && element.valueSet.isNotEmpty()) {
             val lowerSet = element.valueSet.mapKeys { it.key.lowercase() }
             val valStr = lowerSet[retVal?.primitiveValue()?.lowercase() ?: ""]
-            if (valStr != null) {
-                val value = FhirPathUtils.evaluate(context, focusResource, bundle, valStr)
-                if (value.isNotEmpty())
-                    retVal = value[0]
+            retVal = if (valStr != null) {
+                StringType(valStr)
+            } else {
+                null
             }
         }
         return retVal

prime-router/src/main/kotlin/fhirengine/translation/hl7/schema/ConfigSchema.kt

@@ -199,6 +199,11 @@ abstract class ConfigSchemaElement(
             addError("Value property is required when using a value set")
         }
 
+        // value set keys and values cannot be null
+        if (valueSet.keys.any { it == null } || valueSet.values.any { it == null }) {
+            addError("Value sets cannot contain null values")
+        }
+
         if (!schema.isNullOrBlank() && schemaRef == null) {
             addError("Missing schema reference for '$schema'")
         }