rest: replace rf_names[0].rf by RESTResponseFormat::UNDEF for code clarity #32884

1. 
   eval-exec commented at 3:22 am on July 6, 2025: contributor

   I’m reviewing the bitcoin’s rest.cpp source code. In the function: ParseDataFormat, rf_names[0].rf is actualy RESTResponseFormat::UNDEF: https://github.com/bitcoin/bitcoin/blob/e3f416dbf7633b2fb19c933e5508bd231cc7e9cf/src/rest.cpp#L48-L57 so it would be more clarity and code readability to use return RESTResponseFormat::UNDEF; to replace return rf_names[0].rf;
2. rest: replace `rf_names[0].rf` by `RESTResponseFormat::UNDEF` for code clarity 6d19815cd4
3. DrahtBot added the label RPC/REST/ZMQ on Jul 6, 2025
4. 
   DrahtBot commented at 3:22 am on July 6, 2025: contributor

   The following sections might be updated with supplementary metadata relevant to reviewers and maintainers.

   Code Coverage & Benchmarks

   For details see: https://corecheck.dev/bitcoin/bitcoin/pulls/32884.

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5. 
   eval-exec commented at 8:03 am on July 7, 2025: contributor

   Friendly request @fanquake to review this PR.

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eval-exec DrahtBot

Labels
RPC/REST/ZMQ