[4.0] deep_equal is missing

[Protowalker]

Godot version

4.0.dev

System information

Windows 10

Issue description

deep_equal was initially implemented by #42625. The code still exists and is still used internally, but has been renamed recursive_equal. Since it's used internally, my assumption is that it is working, and just hasn't been re-exposed. https://github.com/godotengine/godot/blob/master/core/variant/array.cpp#LL121C22-L121C22

Steps to reproduce

1. Enter a gdscript file.
2. Call deep_equal({}, {})
3. A "not defined" error will appear.
4. Call recursive_equal({}, {})
5. A "not defined" error will appear.

Minimal reproduction project

N/A

[YuriSizov]

In Godot 4 arrays and dictionaries are compared by value, and that comparison is performed internally by recursive_equal. This means you can simply use == and != to compare.