Politely ask people not to submit issues to add support for unknown keyboards. (#19737)

.github/ISSUE_TEMPLATE/feature_request.yml

@@ -7,6 +7,9 @@ body:
     attributes:
       value: |
         Provide a general summary of the changes you want in the title above.
+
+        Please refrain from asking maintainers to add support for specific keyboards -- it is unlikely they will have hardware available, and will not be able to help.
+        Your best bet is to take the initiative, add support, then submit a PR yourself.
   - type: checkboxes
     attributes:
       label: Feature Request Type
@@ -18,4 +21,4 @@ body:
   - type: textarea
     attributes:
       label: Description
-      description: A few sentences describing what it is that you'd like to see in QMK. Additional information (such as links to spec sheets, licensing info, other related issues or PRs, etc) would be helpful.
+      description: A few sentences describing what it is that you'd like to see in QMK. Additional information (such as links to spec sheets, licensing info, other related issues or PRs, etc) would be helpful.

.github/ISSUE_TEMPLATE/other_issues.yml

@@ -10,7 +10,10 @@ body:
     attributes:
       value: |
         Please check [https://docs.qmk.fm/#/support](https://docs.qmk.fm/#/support) for additional resources first. If that doesn't answer your question, choose the bug report template instead, as that may be more appropriate.
+
+        Please refrain from asking maintainers to add support for specific keyboards -- it is unlikely they will have hardware available, and will not be able to help.
+        Your best bet is to take the initiative, add support, then submit a PR yourself.
   - type: textarea
     attributes:
       label: Issue Description
-      description: Describe your issue in as much detail as possible.
+      description: Describe your issue in as much detail as possible.