docs: Suggest checking `zed_extension_api` compatibility (#30474)

Jens Krause created 

Or your extension might not work as expected. Or you have to downgrade
`zed_extension_api` later. Happened
[here](https://github.com/sectore/zed-just-ls/issues/2) or
[here](https://github.com/zed-extensions/ruby/commit/842b0cdb6995e692552645c0584ecc9991c589b1)
recently.

Release Notes:

- N/A

Change summary

docs/src/extensions/developing-extensions.md | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

Detailed changes

docs/src/extensions/developing-extensions.md 🔗 

@@ -70,7 +70,7 @@ crate-type = ["cdylib"]
 zed_extension_api = "0.1.0"
 ```
 
-Make sure to use the latest version of the [`zed_extension_api`](https://crates.io/crates/zed_extension_api) available on crates.io.
+Use the latest version of the [`zed_extension_api`](https://crates.io/crates/zed_extension_api) available on crates.io. Make sure it's still [compatible with Zed versions](https://github.com/zed-industries/zed/blob/main/crates/extension_api#compatible-zed-versions) you want to support.
 
 In the `src/lib.rs` file in your Rust crate you will need to define a struct for your extension and implement the `Extension` trait, as well as use the `register_extension!` macro to register your extension: