Fix: Remove pull_request event from preview deploys (#109)

* Fix: Whitespace indentation for preview deploy

* Fix: Try referencing branch not commit sha

* Update preview.yaml

* Fix: PRs not deploying to preview

* Update preview.yaml

* Fix: Prevent duplicate deploy for push to a pr

* Remove unnecessary `pull_request` event

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

Author: IAmHughes

.github/workflows/preview.yaml

@@ -4,9 +4,6 @@ on:
     branches:
       - "**"
       - "!master"
-    pull_request:
-      branches:
-        - "**"
 jobs:
   preview:
     name: Preview