Wrong indentation: Parser error lacking description

Code in question:
```hs
let i = 1
j = 2
in ...
```

Error message:
```
site.hs:104:3: error: parse error on input ‘j’
|
104 | j = 2
| ^
```
(there are 103 lines above this let clause, but surely those parts are irrelevant)

Suggested Improvements:
```
site.hs:104:3: error: parser error on input 'j'
`let` clause require indenting at least 3 spaces
103 | let i = 1
104 | j = 2
| ^
```

Or, at least
`error: parser error on input 'j' (likely incorrect indentation)`

There should be similar class of errors, but let-clause related ones were the most frequent and problematic.