Updates the deprecation message for implicit incompatible float to int conversion from:
```
Implicit conversion from non-compatible float %.*H to int in %s on line %d
```
to
```
Implicit conversion from float %.*H to int loses precision in %s on line %d
```
Related: #6661
array_column() reimplements array key handling in a way that does
not match standard array key behavior in PHP. Avoid this by making
use of the standard API.
Of course, there is a minor backwards compatibilty break here,
e.g. people could be relying on objects getting cast to string
instead of throwing.
Closes GH-5487.
