gpgconf: add page (#8616)

* gpgconf: add page

* gpgconf: fix formatting

pages/common/gpgconf.md

@@ -0,0 +1,24 @@
+# gpgconf
+
+> Modify .gnupg home directories.
+> More information: <https://www.gnupg.org/documentation/manuals/gnupg/gpgconf.html>.
+
+- List all components:
+
+`gpgconf --list-components`
+
+- List the directories used by gpgconf:
+
+`gpgconf --list-dirs`
+
+- List all options of a component:
+
+`gpgconf --list-options {{component}}`
+
+- List programs and test whether they are runnable:
+
+`gpgconf --check-programs`
+
+- Reload a component:
+
+`gpgconf --reload {{component}}`