### Godot version

4.0.3

### System information

Windows 10

### Issue description

When loading files from a `pck` generated by Godot, file paths must match the exact string path that they were packed in.

Usually when loading files using `FileAccess`, redundant `/`s will be handled correctly. For example, `res://my//path////here` will resolve to `res://my/path/here`. This is not true for `pck`s.

---

Assuming the default `icon.svg` file has been moved into a new directory at `res://assets/`

```gdscript
# This is valid
FileAccess.open("res://assets/icon.svg", FileAccess.READ)
# This is also valid
FileAccess.open("res://assets//////icon.svg", FileAccess.READ)
```

When loading from a `pck`, the path must match exactly.

```gdscript
var packer := PCKPacker.new()
packer.pck_start("res://test.pck")
packer.add_file("res://my//path/icon.svg", "res://assets/icon.svg")
packer.flush()

ProjectSettings.load_resource_pack("res://test.pck")

# This is valid
FileAccess.open("res://my//path/icon.svg", FileAccess.READ)

# This is not valid
FileAccess.open("res://my/path/icon.svg", FileAccess.READ)
# This is also not valid
FileAccess.open("res://my//path/////icon.svg", FileAccess.READ)
```

### Steps to reproduce

Create a `pck` file and start adding files.

Load the `pck` and try to access files with redundant `/`s (or with the correct number of `/`s, if the files were added with redundant `/`s).

### Minimal reproduction project

Available as a repo here: https://github.com/you-win/pck-loading-inconsistency

Available as a zip:
[pck_loading_inconsistency.zip](https://github.com/godotengine/godot/files/11525206/pck_loading_inconsistency.zip)

ERR_PRINT("Can't open pack-referenced file.");
	return ERR_UNAVAILABLE;
}
bool FileAccessPack::is_open() const {
	if (f.is_valid()) {
		return f->is_open();
	} else {
		return false;
	}
}
void FileAccessPack::seek(uint64_t p_position) {
	ERR_FAIL_COND_MSG(f.is_null(), "File must be opened before use.");
	if (p_position > pf.size) {
		eof = true;
	} else {
		eof = false;
	}
	f->seek(off + p_position);
	pos = p_position;
}
void FileAccessPack::seek_end(int64_t p_position) {
	seek(pf.size + p_position);
}
uint64_t FileAccessPack::get_position() const {
	return pos;
}
uint64_t FileAccessPack::get_length() const {
	return pf.size;
}
bool FileAccessPack::eof_reached() const {