Fix license key in Cargo.toml

The Cargo manifest format requires a specific syntax for specifying the license key. `MIT/Apache-2.0` is invalid in that syntax, so some tools might not recognize the license. You can read more about the syntax in [the Cargo reference format docs](https://doc.rust-lang.org/cargo/reference/manifest.html#the-license-and-license-file-fields).

Instead, we now use `MIT OR Apache-2.0`, which is the intended way to write this license.

Cargo.toml

@@ -7,7 +7,7 @@ description = "Your Own Level Editor Creation Kit"
 version = "0.17.0"
 edition = "2021"
 authors = ["IdanArye <[email protected]>"]
-license = "MIT/Apache-2.0"
+license = "MIT OR Apache-2.0"
 repository = "https://github.com/idanarye/bevy-yoleck"
 documentation = "https://docs.rs/bevy-yoleck"
 readme = "README.md"