Update regression test with new reference data accordingly to...

Update regression test with new reference data accordingly to https://git.rz.tu-bs.de/irmb/VirtualFluids_dev/-/merge_requests/209

regression-tests/flow_around_cylinder_test.sh

@@ -4,7 +4,7 @@ source ./regression-tests/__regression_test_executer.sh
 
 
 # 1. set reference data directory (must match the folder structure in https://github.com/irmb/test_data)
-REFERENCE_DATA_DIR=regression_tests/cpu/FlowAroundCylinder_2023_04
+REFERENCE_DATA_DIR=regression_tests/cpu/FlowAroundCylinder_2023_06
 
 # 2. set cmake flags for the build of VirtualFluids
 CMAKE_FLAGS="--preset=make_cpu -DCMAKE_BUILD_TYPE=Release"