Restore thunks on any exception

There's no reason to restrict this to Error exceptions. This shouldn't
matter to #1407 since the repl doesn't catch non-Error exceptions
anyway, but you never know...

src/libexpr/eval-inline.hh

@@ -33,7 +33,7 @@ void EvalState::forceValue(Value & v, const Pos & pos)
             v.type = tBlackhole;
             //checkInterrupt();
             expr->eval(*this, *env, v);
-        } catch (Error & e) {
+        } catch (...) {
             v.type = tThunk;
             v.thunk.env = env;
             v.thunk.expr = expr;