README.md: fix a small typo

Signed-off-by: Lukas Fleischer <lfleischer@archlinux.org>

README.md

@@ -9,7 +9,7 @@ and installed using the Arch Linux package manager `pacman`.
 The aurweb project includes
 
 * A web interface to search for packaging scripts and display package details.
-* A SSH/Git interface to submit and update packages and package meta data.
+* An SSH/Git interface to submit and update packages and package meta data.
 * Community features such as comments, votes, package flagging and requests.
 * Editing/deletion of packages and accounts by Trusted Users and Developers.
 * Area for Trusted Users to post AUR-related proposals and vote on them.