github: automatically close pull requests

This leverages the mistaken-pull-closer GitHub app
to automatically close any GitHub pull requests.
The submitter will receive a notice pointing them
to the SPDK contribution guidelines for Gerrit
instead.

Signed-off-by: Jim Harris <james.r.harris@intel.com>
Change-Id: Ie8ab095b8b62cafa813427187b878df96ec87b7c
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/6034
Reviewed-by: Vasuki Manikarnike <vasuki.manikarnike@hpe.com>
Reviewed-by: Tomasz Zawadzki <tomasz.zawadzki@intel.com>
Reviewed-by: Paul Luse <paul.e.luse@intel.com>
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>

.github/mistaken-pull-closer.yml

@@ -0,0 +1,10 @@
+filters:
+  - true
+
+commentBody: |
+  Thanks for your contribution!  Unfortunately, we don't use GitHub pull
+  requests to manage code contributions to this repository.  Instead, please
+  see https://spdk.io/development which provides instructions on how to
+  submit patches to the SPDK Gerrit instance.
+
+addLabel: false