neovim: Add issue templates to discourage PRs on deploy repo (#2591)

## Checklist

- [-] I have added
[tests](https://www.cursorless.org/docs/contributing/test-case-recorder/)
- [-] I have updated the
[docs](https://github.com/cursorless-dev/cursorless/tree/main/docs) and
[cheatsheet](https://github.com/cursorless-dev/cursorless/tree/main/cursorless-talon/src/cheatsheet)
- [-] I have not broken the cheatsheet

Author: pokey

cursorless.nvim/.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,5 @@
+blank_issues_enabled: false
+contact_links:
+  - name: Create issue on cursorless-dev/cursorless
+    url: https://github.com/cursorless-dev/cursorless/issues/new
+    about: Please file issues on the main Cursorless repository