Update pull_request_template.md

Add VIA userspace keymap link requirement and to checklist

.github/pull_request_template.md

@@ -18,11 +18,20 @@
 <!--- IF THERE IS NO LINK TO SHOW VIA SUPPORT IS IN QMK MASTER ALREADY, -->
 <!--- THIS PR WILL BE CLOSED IMMEDIATELY FOR WORKFLOW REASONS.  -->
 
+## VIA Keymap Pull Request
+
+<!--- Add your VIA keymap PR here -->
+<!--- PR to https://github.com/the-via/qmk_userspace_via/pulls -->
+
+<!--- IF THERE IS NO LINK TO SHOW VIA KEYMAP PR, -->
+<!--- THIS PR WILL BE CLOSED IMMEDIATELY FOR WORKFLOW REASONS.  -->
+
 ## Checklist
 
 <!--- Put an `x` in all the boxes that apply. -->
 
 - [ ] The VIA support for this keyboard is **MERGED** in QMK master already **(MANDATORY)**
+- [ ] VIA keymap is **MERGED** in VIA userspace master already **(MANDATORY)**
 - [ ] The VIA definition follows the guide here: https://caniusevia.com/docs/layouts
 - [ ] I have a V3 JSON version for this keyboard definition.**(MANDATORY)**
 - [ ] I have formatted the JSON file to have consistent formatting with the rest of the repository.