chore: create flakybot.yaml to change default issue priority (#737)

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- [x] Make sure to open an issue as a [bug/issue](https://togithub.com/googleapis/nodejs-logging-bunyan/issues/new/choose) before writing your code!  That way we can discuss the change, evaluate designs, and agree on the general idea
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Fixes #<issue_number_goes_here> 🦕

Author: cindy-peng

.github/flakybot.yaml

@@ -0,0 +1,16 @@
+# Copyright 2024 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+issuePriority: p2
+