Add merge policy to contibuting guide (devopsdays#5936)

closes devopsdays#5935 

Makes clear that PRs are merged immediately, and references the workflow doc so new contributors can find alternate solutions to opening WIP PRs.

CONTRIBUTING.md

@@ -48,7 +48,7 @@ Before starting any new change, it is essential that you `rebase` your local rep
 
 
  This confirms you are on the master branch locally, and then applies the changes from the upstream to your copy.
- 
+
 
 Create a new local [branch](https://help.github.com/articles/about-branches/) for your changes. This helps to keep things tidy!
 
@@ -75,6 +75,12 @@ Make your changes, test them locally (see above), then push that branch up to `o
 1. If you are proposing a change that affects the overall site, and is not tied to an existing issue, please open a [new issue](https://github.com/devopsdays/devopsdays-theme/issues) so that it can be discussed by the team, prior to submitting a pull request.
 1. If you're using CRLF line terminators (like on Windows), the site won't build correctly if the first `+++` line of frontmatter in speaker and program files ends in a space like `+++ `. The [workaround](https://github.com/devopsdays/devopsdays-theme/issues/652) is to remove the trailing space.
 
+### How Changes are Merged
+- A maintainer will merge the PR if it is mergable, as soon as the checks pass.
+- If you do not want your PR merged immediately, in most cases you should not open the PR.
+- Our [workflow guide](https://github.com/devopsdays/devopsdays-web/blob/master/utilities/docs/workflow/README.md) provides solutions to most `WIP` use cases without opening a PR.
+- Questions about specific cases not covered in the guide can be be asked in the #website channel on devopsdays slack.
+
 ### Only make changes to event content files
 "Content" means anything inside the `/content/...`, `/data/...`, or `/static/...` directories.