MC-5710: Beta docs tutorial

Fix heading capitalization consistencies

Author: bdenham

docs/getting-started/install-pagebuilder.md

@@ -4,7 +4,7 @@
 
 You must be an active member in the Page Builder EAP program and have submitted your MAGEID to be provided access to the Page Builder composer packages through `repo.magento.com`. If you have not done so, or are experiencing problems please contact us at `pagebuilderEAP@adobe.com`. 
 
-## Installation Steps
+## Installation steps
 
 1. Upgrade an existing project to Magento 2.3.0 Commerce or install a fresh copy. Instructions for installation can be found [here](https://devdocs.magento.com/guides/v2.3/install-gde/bk-install-guide.html). **Use the MAGEID assigned to you when you signed up to the program.**
 
@@ -28,7 +28,7 @@ This can be install by completing a `composer update` within your project.
 
 ## Troubleshooting
 
-### Composer Installation issues
+### Composer installation issues
 
 If you run into the following issue:
 

docs/getting-started/introduction.md

@@ -83,9 +83,9 @@ We appreciate any and all contributions to PageBuilder. If you are interested in
 
 ## Page Builder updates from the Magento core team
 
-We will push new beta releases once a week, including work from the backlog. We don't expect any large breaking changes, but we  will communicate them to you if the need arises.
+We will push new beta releases once a week, including work from the backlog. We don't expect any large breaking changes, but we will communicate them to you if the need arises.
 
-## Contact Us
+## Contact us
 
 To participate in technical discussions and ask questions, join us in [Slack], where a number of Page Builder team members are present.