fix nominal voltage order (#257)

Signed-off-by: Etienne LESOT <[email protected]>

Author: EtienneLt

src/main/java/org/gridsuite/network/map/NetworkMapController.java

@@ -176,6 +176,6 @@ public List<Country> getCountries(@Parameter(description = "Network UUID") @Path
     })
     public List<Double> getNominalVoltages(@Parameter(description = "Network UUID") @PathVariable("networkUuid") UUID networkUuid,
                                            @Parameter(description = "Variant ID") @RequestParam(name = "variantId", required = false) String variantId) {
-        return networkMapService.getNominalVoltages(networkUuid, variantId).stream().sorted().toList();
+        return networkMapService.getNominalVoltages(networkUuid, variantId).stream().sorted(Comparator.reverseOrder()).toList();
     }
 }

src/test/java/org/gridsuite/network/map/NetworkMapControllerTest.java

@@ -2456,8 +2456,8 @@ void shouldReturnNullableSubstationIdForVoltageLevel() throws Exception {
 
     @Test
     void shouldReturnNominalVoltages() throws Exception {
-        succeedingTestForNominalVoltages(NETWORK_UUID, null, List.of(24.0, 150.0, 225.0, 380.0).toString());
-        succeedingTestForNominalVoltages(NETWORK_UUID, VARIANT_ID_2, List.of(24.0, 150.0, 225.0, 380.0, 400.0).toString());
+        succeedingTestForNominalVoltages(NETWORK_UUID, null, List.of(380.0, 225.0, 150.0, 24.0).toString());
+        succeedingTestForNominalVoltages(NETWORK_UUID, VARIANT_ID_2, List.of(400.0, 380.0, 225.0, 150.0, 24.0).toString());
     }
 
     @Test