Fixed capitalization (Community)

Author: Linda-Editor

docs/toc.yml

@@ -4766,9 +4766,9 @@
     href: https://aka.ms/spdev-issues
   - name: Submit feature requests
     href: http://aka.ms/spdev-uservoice
-  - name: SharePoint Developer Videos on YouTube
+  - name: SharePoint developer videos on YouTube
     href: http://aka.ms/spdev-videos
-  - name: Office Development on Twitter
+  - name: Office development on Twitter
     href: https://twitter.com/officedev
   - name: SharePoint developer forum
-    href: http://aka.ms/spdev-community
+    href: http://aka.ms/spdev-community