Disable use of TBB aka OneAPI for tests due to some undiagnosed inclusion
and/or linker issue: https://github.com/boostorg/unordered/issues/222

--- libs/unordered/test/Jamfile.v2.orig	2025-08-06 18:49:15 UTC
+++ libs/unordered/test/Jamfile.v2
@@ -39,6 +39,8 @@ project
         <toolset>gcc:<warnings-as-errors>on
         <toolset>clang:<warnings-as-errors>on
         <toolset>msvc:<warnings-as-errors>on
+
+         <cxxflags>-DBOOST_UNORDERED_DISABLE_PARALLEL_ALGORITHMS
     ;
 
 path-constant BOOST_UNORDERED_TEST_DIR : . ;