FIX: Incorrect Group index in UI for survey

Author: Pa-Touche

sormas-api/src/main/java/de/symeda/sormas/api/externalmessage/survey/PatchField.java

@@ -64,8 +64,8 @@ public PatchField setGroupIndex(@Nullable Integer groupIndex) {
 	}
 
 	@JsonIgnore
-	public Optional<Integer> getGroupNumber() {
-		return Optional.ofNullable(groupIndex).map(index -> index + 1);
+	public Optional<Integer> getGroupIndexAsOptional() {
+		return Optional.ofNullable(groupIndex);
 	}
 
 	@JsonValue

sormas-ui/src/main/java/de/symeda/sormas/ui/externalmessage/surveyresponse/SurveyResponseDisplayUtils.java

@@ -14,7 +14,7 @@ private SurveyResponseDisplayUtils() {
 	}
 
 	public static String resolveFieldName(PatchField patchField, DisplayablePartialRetrievalResponse displayData) {
-		String groupNumberPrefix = patchField.getGroupNumber().map(integer -> integer + ": ").orElse("");
+		String groupNumberPrefix = patchField.getGroupIndexAsOptional().map(integer -> integer + ": ").orElse("");
 		String fieldPath = patchField.getField();
 
 		DisplayableFieldInfo info = displayData.getFieldInfoDictionary().get(fieldPath);