Add license to Gleam extension (#8730)

Marshall Bowers created 

This PR adds a license to the Gleam extension crate, since the bundling
script was unhappy that it didn't have one.

Since extensions like this one may ultimately live outside of Zed
itself, I went with the Apache 2.0 license.

Release Notes:

- N/A

Change summary

extensions/gleam/Cargo.toml     | 2 ++
extensions/gleam/LICENSE-APACHE | 1 +
2 files changed, 3 insertions(+)

Detailed changes

extensions/gleam/Cargo.toml 🔗 

@@ -2,6 +2,8 @@
 name = "zed_gleam"
 version = "0.0.1"
 edition = "2021"
+publish = false
+license = "Apache-2.0"
 
 [dependencies]
 zed_extension_api = { path = "../../crates/extension_api" }