Rewrite install_into_rootfs doc comment to omit temp-file detail

src/inject.rs

@@ -87,8 +87,8 @@ pub fn build_exec_script(command: &str, env: &[String], working_dir: Option<&str
     lines
 }
 
-/// Write `content` to a temp file and install it into the mounted rootfs at
-/// `<mount>/slim/<name>` with the given mode.
+/// Install `content` into the mounted rootfs at `<mount>/slim/<name>` with
+/// the given mode.
 fn install_into_rootfs(mount: &str, name: &str, mode: &str, content: &str) -> Result<()> {
     let temp = tempfile::NamedTempFile::new()?;
     fs::write(temp.path(), content)?;