Ignore test issue-45696-scribble-on-boxed-borrow.rs in Polonius compare mode

Once again, the difference is in the test construction, it is ignored in compare-mode NLL and tested manually with revisions, and fails because the `migrate` revision is ran with `-Zpolonius`. There is no actual difference in the errors output by NLLs and Polonius.

Author: lqd

src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.migrate.stderr

@@ -1,5 +1,5 @@
 warning[E0713]: borrow may still be in use when destructor runs
-  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:51:5
+  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:52:5
    |
 LL | fn scribbled<'a>(s: Scribble<'a>) -> &'a mut u32 {
    |              -- lifetime `'a` defined here
@@ -14,7 +14,7 @@ LL | }
    = note: for more information, try `rustc --explain E0729`
 
 warning[E0713]: borrow may still be in use when destructor runs
-  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:62:5
+  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:63:5
    |
 LL | fn boxed_scribbled<'a>(s: Box<Scribble<'a>>) -> &'a mut u32 {
    |                    -- lifetime `'a` defined here
@@ -29,7 +29,7 @@ LL | }
    = note: for more information, try `rustc --explain E0729`
 
 warning[E0713]: borrow may still be in use when destructor runs
-  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:73:5
+  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:74:5
    |
 LL | fn boxed_boxed_scribbled<'a>(s: Box<Box<Scribble<'a>>>) -> &'a mut u32 {
    |                          -- lifetime `'a` defined here
@@ -44,7 +44,7 @@ LL | }
    = note: for more information, try `rustc --explain E0729`
 
 error: compilation successful
-  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:80:1
+  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:81:1
    |
 LL | / fn main() {
 LL | |     let mut x = 1;

src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.nll.stderr

@@ -1,5 +1,5 @@
 error[E0713]: borrow may still be in use when destructor runs
-  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:51:5
+  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:52:5
    |
 LL | fn scribbled<'a>(s: Scribble<'a>) -> &'a mut u32 {
    |              -- lifetime `'a` defined here
@@ -10,7 +10,7 @@ LL | }
    | - here, drop of `s` needs exclusive access to `*s.0`, because the type `Scribble<'_>` implements the `Drop` trait
 
 error[E0713]: borrow may still be in use when destructor runs
-  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:62:5
+  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:63:5
    |
 LL | fn boxed_scribbled<'a>(s: Box<Scribble<'a>>) -> &'a mut u32 {
    |                    -- lifetime `'a` defined here
@@ -21,7 +21,7 @@ LL | }
    | - here, drop of `s` needs exclusive access to `*s.0`, because the type `Scribble<'_>` implements the `Drop` trait
 
 error[E0713]: borrow may still be in use when destructor runs
-  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:73:5
+  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:74:5
    |
 LL | fn boxed_boxed_scribbled<'a>(s: Box<Box<Scribble<'a>>>) -> &'a mut u32 {
    |                          -- lifetime `'a` defined here

src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.rs

@@ -7,6 +7,7 @@
 
 // revisions: nll migrate
 // ignore-compare-mode-nll
+// ignore-compare-mode-polonius
 
 // This test is going to pass in the migrate revision, because the AST-borrowck
 // accepted this code in the past (see notes below). So we use `#[rustc_error]`