boost{177,178,179,180,181,182,183}: conditionalize stacktrace flag

This library was introduced in Boost 1.85.

Fixes: 3e2ceab201

pkgs/development/libraries/boost/generic.nix

@@ -89,6 +89,8 @@ let
       "link=${link}"
       "-sEXPAT_INCLUDE=${expat.dev}/include"
       "-sEXPAT_LIBPATH=${expat.out}/lib"
+    ]
+    ++ lib.optionals (lib.versionAtLeast version "1.85") [
       (
         # The stacktrace from exception feature causes memory leaks when built
         # with libc++. For all other standard library implementations, i.e.
@@ -99,9 +101,8 @@ let
         else
           "define=BOOST_STACKTRACE_LIBCXX_RUNTIME_MAY_CAUSE_MEMORY_LEAK"
       )
-
-      # TODO: make this unconditional
     ]
+    # TODO: make this unconditional
     ++
       lib.optionals
         (