Merge #19706: refactor: make EncodeBase58{Check} consume Spans

356988e200 util: make EncodeBase58Check consume Spans (Sebastian Falbesoner)
f0fce0675d util: make EncodeBase58 consume Spans (Sebastian Falbesoner)

Pull request description:

  This PR improves the interfaces for the functions `EncodeBase58{Check}` by using Spans, in a similar fashion to e.g. PRs #19660, #19687. Note that on the master branch there are currently two versions of `EncodeBase58`: one that takes two pointers (marking begin and end) and another one that takes a `std::vector<unsigned char>` const-ref. The PR branch only leaves one generic Span-interface, both simplifying the interface and allowing more generic containers to be passed. The same is done for `EncodeBase58Check`, where only one interface existed but it's more generic now (e.g. a std::array can be directly passed, as done in the benchmarks).

ACKs for top commit:
  laanwj:
    Code review ACK 356988e200

Tree-SHA512: 47cfccdd7f3a2d4694bb8785e6e5fd756daee04ce1652ee59a7822e7e833b4a441ae9362b9bd67ea020d2b5b7d927629c9addb6abaa9881d8564fd3b1257f512

src/test/base58_tests.cpp

@@ -33,7 +33,7 @@ BOOST_AUTO_TEST_CASE(base58_EncodeBase58)
         std::vector<unsigned char> sourcedata = ParseHex(test[0].get_str());
         std::string base58string = test[1].get_str();
         BOOST_CHECK_MESSAGE(
-                    EncodeBase58(sourcedata.data(), sourcedata.data() + sourcedata.size()) == base58string,
+                    EncodeBase58(sourcedata) == base58string,
                     strTest);
     }
 }