[CMake] Use imported executable targets for finding Qt uic/rcc

Commit 024bde6 ("Update FindPySide2Tools.cmake") removed the
versioned names of uic/rcc, which are at least used on openSUSE
and Fedora.

Instead of determining the path of uic/rcc manually, just use
the imported executable targets. rcc comes from QtCore, while
uic comes from QtWidgets.

Fixes FreeCAD#6445.

cMake/FindPySide2Tools.cmake

@@ -23,7 +23,7 @@ endif(WIN32 OR ${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
 # Since Qt v5.14, pyside2-uic and pyside2-rcc are directly provided by Qt5Core uic and rcc, with '-g python' option
 # We test Qt5Core version to act accordingly
 
-FIND_PACKAGE(Qt5Core)
+FIND_PACKAGE(Qt5 COMPONENTS Core Widgets)
 
 IF(Qt5Core_VERSION VERSION_LESS 5.14)
   # Legacy (< 5.14)
@@ -33,10 +33,14 @@ IF(Qt5Core_VERSION VERSION_LESS 5.14)
   set(RCCOPTIONS "")
 ELSE()
   # New (>= 5.14)
-  FIND_PROGRAM(PYSIDE2UICBINARY NAMES uic )#pyside2-uic)
-  set(UICOPTIONS "--generator=python")
-  FIND_PROGRAM(PYSIDE2RCCBINARY NAMES  rcc )#pyside2-rcc)
-  set(RCCOPTIONS "--generator=python" "--compress-algo=zlib" "--compress=1")
+  if (TARGET Qt::uic)
+    get_property(PYSIDE2UICBINARY TARGET Qt::uic PROPERTY LOCATION)
+    set(UICOPTIONS "--generator=python")
+  endif()
+  if (TARGET Qt::rcc)
+    get_property(PYSIDE2RCCBINARY TARGET Qt::rcc PROPERTY LOCATION)
+    set(RCCOPTIONS "--generator=python" "--compress-algo=zlib" "--compress=1")
+  endif()
 ENDIF(Qt5Core_VERSION VERSION_LESS 5.14)
 
 MACRO(PYSIDE_WRAP_UI outfiles)
@@ -93,11 +97,8 @@ MACRO(PYSIDE_WRAP_RC outfiles)
   ENDFOREACH(it)
 ENDMACRO (PYSIDE_WRAP_RC)
 
-IF(EXISTS ${PYSIDE2UICBINARY} AND EXISTS ${PYSIDE2RCCBINARY})
-   set(PYSIDE2_TOOLS_FOUND TRUE)
-ENDIF(EXISTS ${PYSIDE2UICBINARY} AND EXISTS ${PYSIDE2RCCBINARY})
-
 if(PYSIDE2RCCBINARY AND PYSIDE2UICBINARY)
+    set(PYSIDE2_TOOLS_FOUND TRUE)
     if (NOT PySide2Tools_FIND_QUIETLY)
         message(STATUS "Found PySide2 tools: ${PYSIDE2UICBINARY}, ${PYSIDE2RCCBINARY}")
     endif (NOT PySide2Tools_FIND_QUIETLY)