Adjust tests to handle Sapling anchor cache

src/gtest/test_mempool.cpp

@@ -61,6 +61,7 @@ public:
                     const uint256 &hashSproutAnchor,
                     const uint256 &hashSaplingAnchor,
                     CAnchorsSproutMap &mapSproutAnchors,
+                    CAnchorsSaplingMap &mapSaplingAnchors,
                     CNullifiersMap &mapSproutNullifiers,
                     CNullifiersMap &mapSaplingNullifiers) {
         return false;