Fix Oracle's token pair deterministic order

[gregtatcam]

High Level Overview of Change

Price Oracle data-series logic uses unordered_map to update the Oracle object. This results in different servers disagreeing on the order of that hash table. Consequently, the generated ledgers will have different hashes. The fix uses map instead to guarantee the order of the token pairs in the data-series.

Type of Change

• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [x] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [ ] Refactor (non-breaking change that only restructures code)
• [ ] Performance (increase or change in throughput and/or latency)
• [ ] Tests (you added tests for code that already exists, or your new feature included in this PR)
• [ ] Documentation update
• [ ] Chore (no impact to binary, e.g. .gitignore, formatting, dropping support for older tooling)
• [ ] Release

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 71.1%. Comparing base (d5e5c3c) to head (cecfdee).

Additional details and impacted files

[](https://app.codecov.io/gh/XRPLF/rippled/pull/5021?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=XRPLF) ```diff @@ Coverage Diff @@ ## develop #5021 +/- ## ======================================= Coverage 71.1% 71.1% ======================================= Files 796 796 Lines 66997 66997 Branches 10982 10979 -3 ======================================= Hits 47635 47635 Misses 19362 19362 ``` | [Files](https://app.codecov.io/gh/XRPLF/rippled/pull/5021?dropdown=coverage&src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=XRPLF) | Coverage Δ | | |---|---|---| | [src/ripple/app/tx/impl/SetOracle.cpp](https://app.codecov.io/gh/XRPLF/rippled/pull/5021?src=pr&el=tree&filepath=src%2Fripple%2Fapp%2Ftx%2Fimpl%2FSetOracle.cpp&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=XRPLF#diff-c3JjL3JpcHBsZS9hcHAvdHgvaW1wbC9TZXRPcmFjbGUuY3Bw) | `100.0% <100.0%> (ø)` | | ... and [3 files with indirect coverage changes](https://app.codecov.io/gh/XRPLF/rippled/pull/5021/indirect-changes?src=pr&el=tree-more&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=XRPLF) [](https://app.codecov.io/gh/XRPLF/rippled/pull/5021?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=XRPLF)