Update topics to sentence case (#19069)

content/github/getting-started-with-github/set-up-git.md

@@ -16,10 +16,10 @@ versions:
   enterprise-server: '*'
   github-ae: '*'
 topics:
-  - pull requests
-  - issues
-  - notifications
-  - accounts
+  - Pull requests
+  - Issues
+  - Notifications
+  - Accounts
 ---
 
 To use Git on the command line, you'll need to download, install, and configure Git on your computer. {% if currentVersion == "free-pro-team@latest" or currentVersion ver_gt "enterprise-server@2.19" or currentVersion == "github-ae@latest" %} You can also install {% data variables.product.prodname_cli %} to use {% data variables.product.product_name %} from the command line. For more information on {% data variables.product.prodname_cli %}, see the [{% data variables.product.prodname_cli %}](https://cli.github.com/manual/) documentation.{% endif %}