chore: delete stale bot (#2264)

The repo is actively maintained, but we've had a bunch of relevant
issues be auto-closed by the bot. I haven't seen other active rulesets
adopt this, so I don't think it makes sense to be the outlier.

Note, I introduced this configuration.

https://github.com/bazelbuild/rules_python/issues/385 as an example
where users have to make comments to prevent things being marked stale.
diff --git a/.github/workflows/stale.yml b/.github/workflows/stale.yml
deleted file mode 100644
index d37121b..0000000
--- a/.github/workflows/stale.yml
+++ /dev/null
@@ -1,73 +0,0 @@
-# Copyright 2023 The Bazel Authors. All rights reserved.
-#
-# 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.
-
-# See https://github.com/marketplace/actions/close-stale-issues
-
-name: Mark stale issues and pull requests
-
-on:
-  schedule:
-  # run at 22:45 UTC daily
-  - cron: "45 22 * * *"
-
-jobs:
-  stale:
-    runs-on: ubuntu-latest
-
-    steps:
-    - uses: actions/stale@v9
-      with:
-        repo-token: ${{ secrets.GITHUB_TOKEN }}
-
-        # NB: We start with very long duration while trimming existing issues,
-        # with the hope to reduce when/if we get better at keeping up with user support.
-
-        # The number of days old an issue can be before marking it stale.
-        days-before-stale: 180
-        # Number of days of inactivity before a stale issue is closed
-        days-before-close: 30
-
-        # If an issue/PR is assigned, trust the assignee to stay involved
-        # Can revisit if these get stale
-        exempt-all-assignees: true
-        # Issues with these labels will never be considered stale
-        exempt-issue-labels: "need: discussion,cleanup"
-
-        # Label to use when marking an issue as stale
-        stale-issue-label: 'Can Close?'
-        stale-pr-label: 'Can Close?'
-
-        stale-issue-message: >
-          This issue has been automatically marked as stale because it has not had
-          any activity for 180 days.
-          It will be closed if no further activity occurs in 30 days.
-
-          Collaborators can add an assignee to keep this open indefinitely.
-          Thanks for your contributions to rules_python!
-
-        stale-pr-message: >
-          This Pull Request has been automatically marked as stale because it has not had
-          any activity for 180 days.
-          It will be closed if no further activity occurs in 30 days.
-
-          Collaborators can add an assignee to keep this open indefinitely.
-          Thanks for your contributions to rules_python!
-
-        close-issue-message: >
-          This issue was automatically closed because it went 30 days without a reply
-          since it was labeled "Can Close?"
-
-        close-pr-message: >
-          This PR was automatically closed because it went 30 days without a reply
-          since it was labeled "Can Close?"