update PR template

Author: patzick

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,12 +1,3 @@
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-name: 1. First PR for Vue Storefront
-about: Is it your first PR for Vue Storefront and you're not sure what to pick? No worries, we got you covered! Pick this template.
-
----
-
-This is my first PR for storefront or i'm not sure which other PR should i choose.
-<!-- If that's correct then just go along with this template. You can click 'preview' above to see how it will be shown at the end -->
-
 ### Related issues
 <!--  Put related issue number which this PR is closing. For example #123 -->