gh-gpg-key: add page (#18163)

* gh-gpg-key: add page

* gh-gpg-key: use path syntax in placeholder

Author: dmmqz

pages/common/gh-gpg-key.md

@@ -0,0 +1,21 @@
+# gh gpg-key
+
+> Manage GPG keys registered with the authorized GitHub account.
+> See also: `gpg`.
+> More information: <https://cli.github.com/manual/gh_gpg-key>.
+
+- List GPG keys in the authorized GitHub account:
+
+`gh gpg-key {{[ls|list]}}`
+
+- Add a GPG key to the authorized GitHub account by specifying the key file:
+
+`gh gpg-key add {{path/to/key_file}}`
+
+- Add a GPG key to the authorized GitHub account by specifying the key ID:
+
+`gpg {{[-a|--armor]}} --export {{key_id}} | gh gpg-key add -`
+
+- Delete a GPG key from the authorized GitHub account:
+
+`gh gpg-key delete {{key_id}}`