Update headings and guidance about headings.

docs/contribute/create-pull-request.md

@@ -23,7 +23,7 @@ Documentation will be published under the [CC BY SA 4.0](https://github.com/kube
 
 {% capture steps %}
 
-### Creating a fork of the Kubernetes documentation repository
+## Creating a fork of the Kubernetes documentation repository
 
 1. Go to the
 [kubernetes/kubernetes.github.io](https://github.com/kubernetes/kubernetes.github.io){: target="_blank"}
@@ -33,18 +33,18 @@ repository.
 Kubernetes documentation repository in your GitHub account. The copy
 is called a *fork*.
 
-### Making your changes
+## Making your changes
 
 1. In your GitHub account, in your fork of the Kubernetes docs, create
 a new branch to use for your contribution.
 
-1. In your new branch, make your changes and commit them. If you want to 
+1. In your new branch, make your changes and commit them. If you want to
 [write a new topic](/docs/contribute/write-new-topic/),
 choose the
 [page type](/docs/contribute/page-templates/)
 that is the best fit for your content.
 
-### Submitting a pull request to the master branch (Current Release)
+## Submitting a pull request to the master branch (Current Release)
 
 If you want your change to be published in the released version Kubernetes docs,
 create a pull request against the master branch of the Kubernetes
@@ -62,7 +62,7 @@ site where you can verify that your changes have rendered correctly.
 If needed, revise your pull request by committing changes to your
 new branch in your fork.
 
-### Submitting a pull request to the <vnext> branch (Upcoming Release)
+## Submitting a pull request to the <vnext> branch (Upcoming Release)
 
 If your documentation change should not be released until the next release of
 the Kubernetes product, create a pull request against the <vnext> branch