Update playbooks_best_practices.rst (#35627)

* Update playbooks_best_practices.rst

If deploying to the first 10 hosts in Boston it should be "-limit boston[0:9]" and the next 10 should be "-limit boston[10:19]". The doc as written would skip the first host (boston[0]) and try to deploy to a host that doesn't exist (boston[20])

* Typo fix

docs/docsite/rst/playbooks_best_practices.rst

@@ -297,10 +297,10 @@ For just my webservers in Boston::
 
     ansible-playbook -i production webservers.yml --limit boston
 
-Forjust the first 10, and then the next 10::
+For just the first 10, and then the next 10::
    
-    ansible-playbook -i production webservers.yml --limit boston[1:10]
+    ansible-playbook -i production webservers.yml --limit boston[0:9]
-    ansible-playbook -i production webservers.yml --limit boston[11:20]
+    ansible-playbook -i production webservers.yml --limit boston[10:19]
 
 And of course just basic ad-hoc stuff is also possible::