Rollup merge of #130349 - ShE3py:break_up_float, r=fmease

Fix `Parser::break_up_float`'s right span

```rs
use std::mem::offset_of;

fn main() {
    offset_of!((u8,), 0.0);
}
```
Before:
```
error[E0609]: no field `0` on type `u8`
    --> ./main.rs:4:25
     |
4    |       offset_of!((u8,), 0.0);
     |  _____--------------------^-
     | |     |
     | |     in this macro invocation
5    | | }
...    |
     |
     = note: this error originates in the macro `offset_of` (in Nightly builds, run with -Z macro-backtrace for more info)

error: aborting due to 1 previous error
```
After:
```
error[E0609]: no field `0` on type `u8`
 --> ./main.rs:4:25
  |
4 |     offset_of!((u8,), 0.0);
  |                         ^

error: aborting due to 1 previous error
```

---
`@rustbot` label +A-parser +D-imprecise-spans

Author: fmease