Update quarto-pub.qmd (#1394)

Simplifying the verbal combination 'are have' to 'have'

(cherry picked from commit e044e00)

Author: PeteArm

docs/publishing/quarto-pub.qmd

@@ -45,7 +45,7 @@ To promote one of your sites to the default site, go to your admin page at <http
 
 ## Multiple Accounts
 
-If you are have multiple Quarto Pub accounts it's important to understand the relationship between the use of accounts in the CLI interface (`quarto publish`) and the use of accounts in your browser (for authenticating and managing sites).
+If you have multiple Quarto Pub accounts it's important to understand the relationship between the use of accounts in the CLI interface (`quarto publish`) and the use of accounts in your browser (for authenticating and managing sites).
 
 When using `quarto publish`, there are a couple of scenarios where a web browser is launched: