Rollup merge of #146490 - Oneirical:uncountable-integer-12, r=jieyouxu

Rehome 26 `tests/ui/issues/` tests to other subdirectories under `tests/ui/` [#5 of Batch #2]

Part of #133895

Methodology:

1. Refer to the previously written `tests/ui/SUMMARY.md`
2. Find an appropriate category for the test, using the original issue thread and the test contents.
3. Add the issue URL at the bottom (not at the top, as that would mess up stderr line numbers)
4. Rename the tests to make their purpose clearer

Inspired by the methodology that Kivooeo was using.

r? ```@jieyouxu```

Author: matthiaskrgr

tests/ui/associated-consts/ambiguous-associated-type-error-78622.rs renamed to tests/ui/associated-types/ambiguous-associated-type-error-78622.rs

@@ -1,5 +1,5 @@
 error[E0308]: mismatched types
-  --> $DIR/mismatched-types-in-trait-implementation-87490.rs:10:5
+  --> $DIR/mismatched-types-in-associated-type-87490.rs:10:5
    |
 LL | fn follow(_: &str) -> <&str as StreamOnce>::Position {
    |                       ------------------------------ expected `usize` because of return type

tests/ui/associated-consts/ambiguous-associated-type-error-78622.stderr renamed to tests/ui/associated-types/ambiguous-associated-type-error-78622.stderr

@@ -1,3 +1,4 @@
+// https://github.com/rust-lang/rust/issues/72076
 trait X {
     type S;
     fn f() -> Self::S {} //~ ERROR mismatched types

tests/ui/mismatched_types/mismatched-types-in-trait-implementation-87490.rs renamed to tests/ui/associated-types/mismatched-types-in-associated-type-87490.rs

@@ -1,5 +1,5 @@
 error[E0308]: mismatched types
-  --> $DIR/issue-72076.rs:3:23
+  --> $DIR/missing-default-associated-type-72076.rs:4:23
    |
 LL |     fn f() -> Self::S {}
    |                       ^^ expected associated type, found `()`

tests/ui/mismatched_types/mismatched-types-in-trait-implementation-87490.stderr renamed to tests/ui/associated-types/mismatched-types-in-associated-type-87490.stderr

@@ -1,5 +1,5 @@
 error[E0070]: invalid left-hand side of assignment
-  --> $DIR/invalid-assignment-in-while-loop-77218.rs:5:19
+  --> $DIR/invalid-assignment-in-while-77218.rs:5:19
    |
 LL |     while Some(0) = value.get(0) {}
    |                -  ^

tests/ui/issues/issue-72076.rs renamed to tests/ui/associated-types/missing-default-associated-type-72076.rs

@@ -1,3 +1,4 @@
+// https://github.com/rust-lang/rust/issues/70724
 fn a() -> i32 {
     3
 }