libs2/tf: SWPROT-8720: fix find_package() for Python3 interpreter (SiliconLabsSoftware#57)

(cherry picked from commit d8b0a256fca227a1de99b714361a7a5b4e4cc0eb)
Forwarded: SiliconLabsSoftware#57
Relate-to: SiliconLabsSoftware#50
Signed-off-by: Philippe Coval <philippe.coval@silabs.com>

Author: Luisky

applications/zpc/components/zwave/zwave_transports/s2/libs/zw-libs2/TestFramework/CMakeLists.txt

@@ -5,7 +5,7 @@ if (NOT TARGET unity)
 
   set(TEST_TOOLS_DIR ${CMAKE_CURRENT_LIST_DIR} CACHE INTERNAL test_tools_dir)
 
-  find_package(PythonInterp)
+  find_package(Python3 COMPONENTS Interpreter)
 
   include(CMakeFunctions.cmake)