Apply test fixes needed for the update to nightly-2024-06-17

Author: tgross35

tests/ui/crashes/ice-6252.stderr

@@ -4,9 +4,7 @@ error[E0412]: cannot find type `PhantomData` in this scope
 LL |     _n: PhantomData,
    |         ^^^^^^^^^^^ not found in this scope
    |
-help: consider importing one of these items
-   |
-LL + use core::marker::PhantomData;
+help: consider importing this struct
    |
 LL + use std::marker::PhantomData;
    |

tests/ui/new_ret_no_self.rs

@@ -363,6 +363,7 @@ impl RetOtherSelf<T> {
     }
 }
 
+#[allow(dependency_on_unit_never_type_fallback)]
 mod issue7344 {
     struct RetImplTraitSelf<T>(T);
 

tests/ui/new_ret_no_self.stderr

@@ -87,7 +87,7 @@ LL | |         }
    | |_________^
 
 error: methods called `new` usually return `Self`
-  --> tests/ui/new_ret_no_self.rs:380:9
+  --> tests/ui/new_ret_no_self.rs:381:9
    |
 LL | /         fn new(t: T) -> impl Into<i32> {
 LL | |
@@ -96,7 +96,7 @@ LL | |         }
    | |_________^
 
 error: methods called `new` usually return `Self`
-  --> tests/ui/new_ret_no_self.rs:402:9
+  --> tests/ui/new_ret_no_self.rs:403:9
    |
 LL | /         fn new(t: T) -> impl Trait2<(), i32> {
 LL | |