rtx-cfd three_d: ignore reasons on the probes (clippy)

Co-Authored-By: Claude Fable 5.1 <[email protected]>

crates/specialized/rtx-cfd/src/solvers/incompressible/three_d/poisson/mod.rs

@@ -1054,7 +1054,7 @@ mod probe {
     }
 
     #[test]
-    #[ignore]
+    #[ignore = "probe: prints the V-cycle symmetry defect across nz and smoothers"]
     fn probe_symmetry() {
         for nz in [1usize, 2, 4] {
             for smoother in [MgSmoother::Lexicographic, MgSmoother::RedBlack] {

crates/specialized/rtx-cfd/tests/three_d_poisson_identity.rs

@@ -211,7 +211,7 @@ fn an_extrusion_in_z_is_z_invariant() {
 }
 
 #[test]
-#[ignore]
+#[ignore = "probe: prints CG iteration counts across nz, coupling and depth"]
 fn probe_iteration_counts() {
     let (nx, ny) = (48, 20);
     let p2 = problem_2d(nx, ny, 7);