feat: add command for viewing gh-fzf's changelog

Under the hood, this just runs > gh fzf release --repo benelan/gh-fzf

gh-fzf

@@ -66,6 +66,7 @@ See \`gh <command> list --help\` for the flag options.
 Other Commands:
   help        Print this help message.
   version     Print the version of gh-fzf.
+  changelog   View gh-fzf's changelog via the release command.
 
 Check out the project homepage for more information, such as keybindings,
 configuration, and examples.
@@ -640,6 +641,7 @@ main() {
         gist | gists | --gist | --gists) gist_cmd "$@" ;;
         workflow | workflows | --workflow | --workflows) workflow_cmd "$@" ;;
         label | labels | --label | --labels) label_cmd "$@" ;;
+        changelog) gh fzf release --repo benelan/gh-fzf ;;
         v | V | -v | -V | version | --version) printf "%s\n" "$GH_FZF_VERSION" ;;
         *) error "invalid command: \"$command\"" ;;
     esac