PHP_EXPAND_PATH broken with bash 5.3.0

### Description

Discover with ion extension
See workaround https://github.com/awesomized/ext-ion/pull/12


With bash 5.3.0 `cd ""` now outputs an error `sh: cd: null directory `and fails
making `PHP_EXPAND_PATH` broken (for `.`)

### PHP Version

```plain
All PHP versions
```

### Operating System

Fedora 43