Update original MedicationStatement lastIssueDate for multiple acute med

When an accute med has multiple issues, we generate individual plan/statement
for each order.

This updates the original statements lastIssueDate to correspond to the
date on its corresponding MedicationRequest[order].

Previously the lastIssueDate was the most recent date of all the orders.

gp2gp-translator/src/main/java/uk/nhs/adaptors/pss/translator/mapper/medication/MedicationRequestMapper.java

@@ -105,6 +105,11 @@ private void generateResourcesForMultipleOrdersLinkedToASingleAcutePlan(ArrayLis
                         resources.add(duplicatedPlan);
                         resources.add(duplicatedMedicationStatement);
                     }
+
+                    final var originalMedicationStatement = getMedicationStatementByPlanId(medicationStatements, plan.getId());
+                    originalMedicationStatement.getExtensionByUrl(MEDICATION_STATEMENT_LAST_ISSUE_DATE_URL).setValue(
+                        orders.get(0).getDispenseRequest().getValidityPeriod().getStartElement()
+                    );
                 }
             });
     }

gp2gp-translator/src/test/java/uk/nhs/adaptors/pss/translator/mapper/medication/MedicationRequestMapperTest.java

@@ -666,6 +666,19 @@ void expectGeneratedMedicationStatementLastIssueDateExtensionSetToValidityPeriod
                 .isEqualTo(latestOrder.getDispenseRequest().getValidityPeriod().getStartElement());
         }
 
+        @Test
+        void expectOriginalMedicationStatementLastIssueDateExtensionSetToValidityPeriodStart() {
+            var resources = medicationRequestMapper
+                    .mapResources(ehrExtract, (Patient) new Patient().setId(PATIENT_ID), List.of(), PRACTISE_CODE
+                    );
+
+            var earliestOrder = getMedicationRequestById(resources, EARLIEST_ORDER_ID);
+            var originalMedicationStatement = getMedicationStatementById(resources, INITIAL_MEDICATION_STATEMENT_ID);
+
+            assertThat(originalMedicationStatement.getExtensionByUrl(MEDICATION_STATEMENT_LAST_ISSUE_DATE_URL).getValue())
+                .isEqualTo(earliestOrder.getDispenseRequest().getValidityPeriod().getStartElement());
+        }
+
         @Test
         void expectOriginalMedicationStatementUnchangedPropertiesAreCopiedToGeneratedMedicationStatement() {
             var resources = medicationRequestMapper