ci: route issue reporting to the server repository

Issues for all Triton components are tracked in
triton-inference-server/server; disable blank issues here and point the
new-issue chooser at the server repository.

TRI-1100

Author: mc-nv

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,5 @@
+blank_issues_enabled: false
+contact_links:
+  - name: Bug report or feature request
+    url: https://github.com/triton-inference-server/server/issues/new/choose
+    about: Please report issues for all Triton Inference Server components in the server repository.