Code Modernization: Pass an appropriate error level to `trigger_error()` in...

Code Modernization: Pass an appropriate error level to `trigger_error()` in `_doing_it_wrong()` and related functions:

* `_deprecated_function()`
* `_deprecated_argument()`
* `_deprecated_constructor()`
* `_deprecated_file()`

The error level passed is `E_USER_DEPRECATED` for the deprecated function group and `E_USER_NOTICE` for `_doing_it_wrong()`.

Props jrf.
Fixes #36561.
Built from https://develop.svn.wordpress.org/trunk@46625


git-svn-id: https://core.svn.wordpress.org/trunk@46422 1a063a9b-81f0-0310-95a4-ce76da25c4cd