"Add FailCheck for known failing tests

Added FAIL_CHECK to indicate that the following test cases are expected to fail due to known issues:
- AdaptToBackend with MetaOp
- AdaptToBackend with MetaOp and constantFolding"

unit_tests/recipes/Test_AdaptToBackend.cpp

@@ -183,6 +183,7 @@
     REQUIRE_NOTHROW(sched.generateScheduling());
     REQUIRE_NOTHROW(sched.generateMemory());
     REQUIRE_NOTHROW(sched.forward());
+    FAIL_CHECK("This test is expected to fail due to known issues.");
  }
 
 //  Interesting test because used a lot for export
@@ -240,9 +241,8 @@
         }
     }
     REQUIRE(cpt == 2);
+    FAIL_CHECK("This test is expected to fail due to known issues.");
  }
  
- 
- 
  }  // namespace Aidge
  
\ No newline at end of file