rename a test which checks long constant evaluation causes dead codes

Author: Shunpoco

tests/ui/consts/do-not-ice-long-constant-evaluation-in-for-loop.rs renamed to tests/ui/consts/long-constant-evaluation-cause-dead-code.rs

@@ -1,13 +1,13 @@
 error: constant evaluation is taking a long time
-  --> $DIR/do-not-ice-long-constant-evaluation-in-for-loop.rs:10:14
+  --> $DIR/long-constant-evaluation-cause-dead-code.rs:10:14
    |
 LL |         [(); loop {}];
    |              ^^^^^^^
    |
    = note: this lint makes sure the compiler doesn't get stuck due to infinite loops in const eval.
            If your compilation actually takes a long time, you can safely allow the lint.
 help: the constant being evaluated
-  --> $DIR/do-not-ice-long-constant-evaluation-in-for-loop.rs:10:14
+  --> $DIR/long-constant-evaluation-cause-dead-code.rs:10:14
    |
 LL |         [(); loop {}];
    |              ^^^^^^^