chore(deps): update rust crate gray_matter to 0.3.0

Author: renovate[bot]

Cargo.lock

@@ -9,7 +9,7 @@ build = "build.rs"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 [build-dependencies]
-gray_matter = "0.2.6"
+gray_matter = "0.3.0"
 poise = "0.6.1"
 serde = "1.0.200"
 serde_json = "1.0.116"