Remove the legacy APR21 setups Refs #2934 #2936

Alternative to !237 (closed) for clearing #2936

To be decided by Physics groups and @v.friese what should be the solution picked (one of the 2 MRs HAS to be picked)

May also be extended to remove also the DEC21 setups depending on decision in #2935

Of interest to @e.clerkin @v.friese @i.selyuzhenkov

setup/setup_sis100_electron_APR21.C

-/** ROOT macro to define the CBM setup sis_100_electron
- **
- ** @author Volker Friese <v.friese@gsi.de>
- ** @author David Emschermann <d.emschermann@gsi.de>
- ** @date   5 February 2016
- **
- **/
-
-// 2020-04-23 - FU - Use exported TOF geometry v16d (same as v16c but
-//                   different file format
-// 2017-11-24 - VF - New default v16g for STS (unit-based)
-// 2017-11-20 - DE - use TRD v17n as new default
-// 2017-05-22 - DE - use TRD v17c as new default
-// 2016-06-27 - DE - use STS v16x as new default, see issue #647
-// 2016-05-19 - VF - Add platform module
-// 2016-02-25 - DE - use STS v16c as new default
-// 2016-02-05 - VF - Replaces former sis100_electron_setup.C,
-//                   now using the CbmSetup class.
-// 2016-01-29 - AL - Use RICH v16a_1e as new default
-// 2015-12-11 - DE - use STS v15c as new default
-// 2015-07-20 - FU - magnet v15a is v12b with correct keeping volume material
-// 2015-07-20 - FU - add material budget files
-// 2015-03-13 - DE - use STS v13y with correct ladder orientation as new default
-// 2015-01-28 - DE - use STS v13x fitting with with PIPE v14l
-// 2015-01-22 - DE - use MVD v14b with PIPE v14l as default
-// 2015-01-19 - DE - use TRD v15a as new default
-// 2014-07-05 - DE - use PIPE v14x as interim solution
-// 2014-07-01 - DE - use PIPE v14f -> overlap with STS
-// 2014-06-30 - DE - use PIPE v14d together with RICH v14a
-// 2014-06-30 - DE - make RICH v14a the new default
-// 2014-06-30 - DE - make TRD v14a the new default
-// 2014-06-25 - DE - define digi files through tags for STS, TRD and TOF
-// 2013-11-05 - DE - switch to trd_v13p geometry
-// 2013-10-11 - DE - add empty string defining the platform
-// 2013-10-07 - DE - pipe_v13d.geo fixes overlap with TOF
-// 2013-10-07 - DE - rich_v13a is not at nominal position 1800mm, but at 1600mm
-// 2013-11-04 - VF - make STS v15b the new default
-//
-
-
-void setup_sis100_electron_APR21()
-{
-
-  // -----  Geometry Tags  --------------------------------------------------
-  TString magnetGeoTag    = "v20a";
-  TString pipeGeoTag      = "v16b_1e";
-  TString mvdGeoTag       = "v20c_tr";
-  TString stsGeoTag       = "v19a";
-  TString richGeoTag      = "v17a_1e";
-  TString trdGeoTag       = "v20b_1e";
-  TString tofGeoTag       = "v20b_1e";
-  TString psdGeoTag       = "v20a";
-  TString platGeoTag      = "v13a";
-  // ------------------------------------------------------------------------
-
-
-  // -----  Magnetic field  -------------------------------------------------
-  TString fieldTag      = "v18a";
-  Double_t fieldZ       = 40.;            // field centre z position
-  Double_t fieldScale   =  1.;            // field scaling factor
-  // ------------------------------------------------------------------------
-
-
-  // -----  Create setup  ---------------------------------------------------
-  CbmSetup* setup = CbmSetup::Instance();
-  if ( ! setup->IsEmpty() ) {
-  	std::cout << "-W- setup_sis100_electron: overwriting existing setup"
-  			      << setup->GetTitle() << std::endl;
-  	setup->Clear();
-  }
-  setup->SetTitle("SIS100 - Electron Setup");
-  setup->SetModule(ECbmModuleId::kMagnet, magnetGeoTag);
-  setup->SetModule(ECbmModuleId::kPipe, pipeGeoTag);
-  setup->SetModule(ECbmModuleId::kMvd, mvdGeoTag);
-  setup->SetModule(ECbmModuleId::kSts, stsGeoTag);
-  setup->SetModule(ECbmModuleId::kRich, richGeoTag);
-  setup->SetModule(ECbmModuleId::kTrd, trdGeoTag);
-  setup->SetModule(ECbmModuleId::kTof, tofGeoTag);
-  setup->SetModule(ECbmModuleId::kPsd, psdGeoTag);
-  setup->SetModule(ECbmModuleId::kPlatform, platGeoTag);
-  setup->SetField(fieldTag, fieldScale, 0., 0., fieldZ);
-  // ------------------------------------------------------------------------
-
-}