fix error testing in taquito auction tests

Author: EGuenz

packages/minter-contracts/test/auction/auction.test.ts

@@ -124,7 +124,7 @@ describe('test NFT auction', () => {
 
     $log.info(`Eve bids 11tz, a 10% raise of previous bid but less than a 10tz increase`);
     const opBid2 = nftAuctionEve.methods.bid(0).send({ amount : 11 });
-    return expect(opBid2).rejects.toHaveProperty('message', 'INVALID_BID_AMOUNT');
+    await expect(opBid2).rejects.toHaveProperty('message', 'INVALID_BID_AMOUNT');
   });
   test('place bid meeting opening price and then raise it by valid amount by min_raise but not min_raise_percent', async () => {
     $log.info(`Alice bids 200tz`);
@@ -134,7 +134,7 @@ describe('test NFT auction', () => {
 
     $log.info(`Eve bids 210tz, a 10tz increase but less than a 10% raise of previous bid `);
     const opBid2 = nftAuctionEve.methods.bid(0).send({ amount : 210 });
-    return expect(opBid2).rejects.toHaveProperty('message', 'INVALID_BID_AMOUNT');
+    await expect(opBid2).rejects.toHaveProperty('message', 'INVALID_BID_AMOUNT');
   });
   test('bid too small should fail', async () => {
     $log.info(`Alice bids 20tz`);