[calls] application: Reword description for the -p flag

[Evangelos Ribeiro Tzaras <devrtz src gnome org>]

commit a2df0226060437c9b0951aaac0c3c1926478ccca
Author: Evangelos Ribeiro Tzaras <devrtz fortysixandtwo eu>
Date:   Mon Oct 18 17:05:48 2021 +0200

    application: Reword description for the -p flag
    
    Closes #338

 src/calls-application.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/calls-application.c b/src/calls-application.c
index 5e740747..ce51dd8a 100644
--- a/src/calls-application.c
+++ b/src/calls-application.c
@@ -655,7 +655,7 @@ calls_application_init (CallsApplication *self)
     {
       "provider", 'p', G_OPTION_FLAG_NONE,
       G_OPTION_ARG_STRING_ARRAY, NULL,
-      _("The name of the plugin to use for the call Provider"),
+      _("The name of the plugin to use as a call provider"),
       _("PLUGIN")
     },
     {