[orca] Change "dedicated command" to "a dedicated command"

[Joanmarie Diggs <joanied src gnome org>]

commit 483adad129804fcbfc94cb10261ecaf63bcc751b
Author: scootergrisen <scootergrisen gmail com>
Date:   Sat Aug 14 21:11:04 2021 +0000

    Change "dedicated command" to "a dedicated command"

 help/C/commands_reading.page | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/help/C/commands_reading.page b/help/C/commands_reading.page
index 3fbd1cdca..58325feb6 100644
--- a/help/C/commands_reading.page
+++ b/help/C/commands_reading.page
@@ -232,7 +232,7 @@
       If you are on a link, <app>Orca</app>'s Basic Where Am I command can be
       used to announce the details associated with the link such as the link type,
       if the link is visited, the site description, and file size. If you would
-      instead prefer dedicated command for this purpose, you can bind <app>Orca</app>'s
+      instead prefer a dedicated command for this purpose, you can bind <app>Orca</app>'s
       Speak Link Details command to a keystroke. Please see <link xref="howto_key_bindings">
       Modifying Keybindings</link> for information on how to do so.
     </p>