[PWGHF] Fix linting errors: struct member order and naming

- Move HfHelper, HfEventSelection, and ccdb declarations after all
  Configurable members in taskD0 and taskDplus (PWGHF struct member order)
- Rename UpcQaHistoConfig to HfUpcQaHistoConfig to comply with PWGHF
  naming convention (structs must start with Hf)

Author: minjungkim12

PWGHF/D2H/Tasks/taskD0.cxx

@@ -162,6 +162,14 @@ struct HfTaskD0 {
   Configurable<float> upcFT0CThreshold{"upcFT0CThreshold", hf_upc::defaults::FT0CThreshold, "FT0-C amplitude threshold for UPC gap determination (a.u.)"};
   Configurable<float> upcZDCThreshold{"upcZDCThreshold", hf_upc::defaults::ZDCThreshold, "ZDC energy threshold for UPC gap determination (a.u.)"};
 
+  HfEventSelection hfEvSel; // event selection and monitoring
+
+  HfHelper hfHelper;
+  ctpRateFetcher mRateFetcher;
+
+  SliceCache cache;
+  Service<o2::ccdb::BasicCCDBManager> ccdb;
+
   HistogramRegistry registry{
     "registry",
     {{"hPtCand", "2-prong candidates;candidate #it{p}_{T} (GeV/#it{c});entries", {HistType::kTH1F, {{360, 0., 36.}}}},

PWGHF/Utils/utilsUpcHf.h

@@ -101,7 +101,7 @@ inline int gapTypeToInt(GapType gap)
 }
 
 /// \brief Struct to hold UPC QA histogram configuration
-struct UpcQaHistoConfig {
+struct HfUpcQaHistoConfig {
   // FT0 histogram configuration
   int ft0Nbins = 1500;
   float ft0Min = 0.f;