Update ExternalProjectDependency based on commontk/Artichoke@388fc33

Tweak test in ExternalProject_Message to avoid warning related to CMP0054

This commit will avoid warning like this one:

//--------------------
CMake Warning (dev) at CMake/ctkMacroCheckExternalProjectDependency.cmake:345 (if):
  Policy CMP0054 is not set: Only interpret if() arguments as variables or
  keywords when unquoted.  Run "cmake --help-policy CMP0054" for policy
  details.  Use the cmake_policy command to set the policy and suppress this
  warning.

  Quoted variables like "SB_SECOND_PASS" will no longer be dereferenced when
  the policy is set to NEW.  Since the policy is not set the OLD behavior
  will be used.
Call Stack (most recent call first):
  CMake/ctkMacroCheckExternalProjectDependency.cmake:596 (ExternalProject_Message)
  CMakeExternals/Log4Qt.cmake:9 (ExternalProject_Include_Dependencies)
  CMake/ctkMacroCheckExternalProjectDependency.cmake:568 (include)
  CMake/ctkMacroCheckExternalProjectDependency.cmake:614 (ExternalProject_Include_Dependencies)
  CMake/ctkBlockCheckDependencies.cmake:132 (ExternalProject_Include_Dependencies)
  CMakeLists.txt:970 (include)
//--------------------
Update ctkMacroBuildQtPlugin to fix CMake warning related to CMP0026

This commit fixes the warnings like the following:

// ----------------------
1>-- Configuring Loadable module: Transforms [qSlicerTransformsModuleExport.h]
1>CMake Warning (dev) at C:/D/P/SonoEQ-0-build/Slicer-build/CTK/CMake/ctkMacroBuildQtPlugin.cmake:168 (get_target_property):
1>  Policy CMP0026 is not set: Disallow use of the LOCATION target property.
1>  Run "cmake --help-policy CMP0026" for policy details.  Use the cmake_policy
1>  command to set the policy and suppress this warning.
1>  The LOCATION property should not be read from target
1>  "qSlicerAnnotationsModuleWidgetsPlugins".  Use the target name directly
1>  with add_custom_command, or use the generator expression $<TARGET_FILE>, as
1>  appropriate.
1>Call Stack (most recent call first):
1>  C:/D/P/SonoEQ-0-build/Slicer-build/CTK/CMake/ctkMacroBuildQtPlugin.cmake:181 (ctkMacroBuildQtPlugin)
1>  Modules/Loadable/Annotations/Widgets/DesignerPlugins/CMakeLists.txt:36 (ctkMacroBuildQtDesignerPlugin)
// ----------------------
Merge branch 'fix-cmake-3.x-warnings'

* fix-cmake-3.x-warnings:
  Update ctkMacroBuildQtPlugin to fix CMake warning related to CMP0026
  Update ExternalProjectDependency based on commontk/Artichoke@388fc33