minor fixes for frontend console errors w/ burnettk

spiffworkflow-frontend/src/rjsf/carbon_theme/BaseInputTemplate/BaseInputTemplate.tsx

@@ -125,6 +125,7 @@ export default function BaseInputTemplate<
           placeholder={DATE_FORMAT_FOR_DISPLAY}
           helperText={commonAttributes.helperText}
           type="text"
+          labelText=""
           size="md"
           value={dateValue}
           autocomplete="off"

spiffworkflow-frontend/src/services/DateAndTimeService.tsx

@@ -41,6 +41,9 @@ const convertDateObjectToFormattedString = (dateObject: Date) => {
 };
 
 const dateStringToYMDFormat = (dateString: string) => {
+  if (dateString === undefined || dateString === null) {
+    return dateString;
+  }
   if (dateString && dateString.match(/^\d{4}-\d{2}-\d{2}$/)) {
     return dateString;
   }