Remove deprecated .github/stale.yml to address #837 (#838) (#860)

SUMMARY
I noticed that even config for probot/stale is present in the repo, but the old issues and PRs weren't marked as stale and not closed by the bot. Investigated and found that this bot was added to community.kubernetes as ansible-collections/community.kubernetes#53 but wasn't moved to kubernetes.core and never worked here.
Moreover, this bot is completely deprecated and down, ref: probot/stale#430
So, the config to be removed.
ISSUE TYPE

Bugfix Pull Request

COMPONENT NAME
.github/stale.yml
ADDITIONAL INFORMATION
Closes #837
Trivial change that not require changelog

Reviewed-by: Mike Graves <mgraves@redhat.com>
(cherry picked from commit eb731cd3a5)

Co-authored-by: Yuriy Novostavskiy <yuriy@novostavskiy.kiev.ua>

.github/stale.yml

@@ -1,60 +0,0 @@
----
-# Configuration for probot-stale - https://github.com/probot/stale
-
-# Number of days of inactivity before an Issue or Pull Request becomes stale
-daysUntilStale: 90
-
-# Number of days of inactivity before an Issue or Pull Request with the stale
-# label is closed. Set to false to disable. If disabled, issues still need to be
-# closed manually, but will remain marked as stale.
-daysUntilClose: 30
-
-# Only issues or pull requests with all of these labels are check if stale.
-# Defaults to `[]` (disabled)
-onlyLabels: []
-
-# Issues or Pull Requests with these labels will never be considered stale. Set
-# to `[]` to disable
-exemptLabels:
-  - security
-  - planned
-  - priority/critical
-  - lifecycle/frozen
-  - verified
-
-# Set to true to ignore issues in a project (defaults to false)
-exemptProjects: false
-
-# Set to true to ignore issues in a milestone (defaults to false)
-exemptMilestones: true
-
-# Set to true to ignore issues with an assignee (defaults to false)
-exemptAssignees: false
-
-# Label to use when marking as stale
-staleLabel: lifecycle/stale
-
-# Limit the number of actions per hour, from 1-30. Default is 30
-limitPerRun: 30
-
-pulls:
-  markComment: |-
-    PRs go stale after 90 days of inactivity.
-    If there is no further activity, the PR will be closed in another 30 days.
-
-  unmarkComment: >-
-    This pull request is no longer stale.
-
-  closeComment: >-
-    This pull request has been closed due to inactivity.
-
-issues:
-  markComment: |-
-    Issues go stale after 90 days of inactivity.
-    If there is no further activity, the issue will be closed in another 30 days.
-
-  unmarkComment: >-
-    This issue is no longer stale.
-
-  closeComment: >-
-    This issue has been closed due to inactivity.