A variety of Cppcheck fixes (#39115)

* Delete unnecessary virtual destructors.

* Fixes for ImportMDHistoWorkspaceBase

The member variable nbins is unused, and was shadowed inside a method.
Also made some variables in that method const.

* AlgorithmDialog missing const in a few places

* Fix some return by reference in FitPropertyBrowser

* Fix several passedByValue Cppcheck warnings

* Further Cppcheck fixes

Author: jclarkeSTFC

buildconfig/CMake/CppCheck_Suppressions.txt.in

@@ -255,7 +255,6 @@ constParameterReference:${CMAKE_SOURCE_DIR}/Framework/Crystal/src/IndexSXPeaks.c
 constVariableReference:${CMAKE_SOURCE_DIR}/Framework/Crystal/src/IndexSXPeaks.cpp:181
 constVariableReference:${CMAKE_SOURCE_DIR}/Framework/Crystal/src/IntegratePeakTimeSlices.cpp:207
 variableScope:${CMAKE_SOURCE_DIR}/Framework/Crystal/src/IntegratePeakTimeSlices.cpp:239
-39004))
 constVariableReference:${CMAKE_SOURCE_DIR}/Framework/Crystal/src/OptimizeCrystalPlacement.cpp:165
 constVariableReference:${CMAKE_SOURCE_DIR}/Framework/Crystal/src/PeakIntegration.cpp:105
 constVariableReference:${CMAKE_SOURCE_DIR}/Framework/Crystal/src/PeakIntensityVsRadius.cpp:184
@@ -318,7 +317,6 @@ constVariable:${CMAKE_SOURCE_DIR}/Framework/CurveFitting/src/Functions/Inelastic
 constVariable:${CMAKE_SOURCE_DIR}/Framework/CurveFitting/src/Functions/InelasticDiffSphere.cpp:70
 constVariable:${CMAKE_SOURCE_DIR}/Framework/CurveFitting/src/Functions/InelasticDiffSphere.cpp:75
 constVariableReference:${CMAKE_SOURCE_DIR}/Framework/CurveFitting/src/Functions/InelasticDiffSphere.cpp:106
-39004))
 constVariableReference:${CMAKE_SOURCE_DIR}/Framework/CurveFitting/src/IFittingAlgorithm.cpp:230
 constVariablePointer:${CMAKE_SOURCE_DIR}/Framework/CurveFitting/src/LatticeDomainCreator.cpp:171
 constVariableReference:${CMAKE_SOURCE_DIR}/Framework/CurveFitting/src/MSVesuvioHelpers.cpp:369