test: replace WtxidFromString with Wtxid::FromHex

The newly introduced Wtxid::FromHex is more robust and removes
the need for a WtxidFromString helper function

src/test/txpackage_tests.cpp

@@ -43,13 +43,6 @@ inline CTransactionRef create_placeholder_tx(size_t num_inputs, size_t num_outpu
     }
     return MakeTransactionRef(mtx);
 }
-
-// Create a Wtxid from a hex string
-inline Wtxid WtxidFromString(std::string_view str)
-{
-    return Wtxid::FromUint256(uint256S(str));
-}
-
 BOOST_FIXTURE_TEST_CASE(package_hash_tests, TestChain100Setup)
 {
     // Random real segwit transaction
@@ -74,9 +67,9 @@ BOOST_FIXTURE_TEST_CASE(package_hash_tests, TestChain100Setup)
     CTransactionRef ptx_3{MakeTransactionRef(tx_3)};
 
     // It's easy to see that wtxids are sorted in lexicographical order:
-    Wtxid wtxid_1{WtxidFromString("0x85cd1a31eb38f74ed5742ec9cb546712ab5aaf747de28a9168b53e846cbda17f")};
-    Wtxid wtxid_2{WtxidFromString("0xb4749f017444b051c44dfd2720e88f314ff94f3dd6d56d40ef65854fcd7fff6b")};
-    Wtxid wtxid_3{WtxidFromString("0xe065bac15f62bb4e761d761db928ddee65a47296b2b776785abb912cdec474e3")};
+    Wtxid wtxid_1{Wtxid::FromHex("85cd1a31eb38f74ed5742ec9cb546712ab5aaf747de28a9168b53e846cbda17f").value()};
+    Wtxid wtxid_2{Wtxid::FromHex("b4749f017444b051c44dfd2720e88f314ff94f3dd6d56d40ef65854fcd7fff6b").value()};
+    Wtxid wtxid_3{Wtxid::FromHex("e065bac15f62bb4e761d761db928ddee65a47296b2b776785abb912cdec474e3").value()};
     BOOST_CHECK_EQUAL(tx_1.GetWitnessHash(), wtxid_1);
     BOOST_CHECK_EQUAL(tx_2.GetWitnessHash(), wtxid_2);
     BOOST_CHECK_EQUAL(tx_3.GetWitnessHash(), wtxid_3);