Rollup merge of #124200 - scrabsha:sasha/->, r=compiler-errors,fmease

Improve handling of expr->field errors

The current message for "`->` used for field access" is the following:

```rust
error: expected one of `!`, `.`, `::`, `;`, `?`, `{`, `}`, or an operator, found `->`
 --> src/main.rs:2:6
  |
2 |     a->b;
  |      ^^ expected one of 8 possible tokens
```

([playground link](https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=7f8b6f4433aa7866124123575456f54e))

This PR tries to address this by adding a dedicated error message and recovery. The proposed error message is:

```
error: `->` used for field access or method call
 --> ./tiny_test.rs:2:6
  |
2 |     a->b;
  |      ^^ help: try using `.` instead
  |
  = help: the `.` operator will dereference the value if needed
```

(feel free to bikeshed it as much as necessary)
tree: 0c4e3c813b9213a85cf937ee29da2f455173d272
  1. .github/
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  4. library/
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  6. src/
  7. tests/
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  10. .gitattributes
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  14. Cargo.lock
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  16. CODE_OF_CONDUCT.md
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