fix: make SIPs exempt from stale bots

[kristw]

SUMMARY

Update Stale bot configuration

[mistercrunch]

LGTM

[codecov-io]

Codecov Report

Merging #7278 into master will increase coverage by 0.21%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #7278      +/-   ##
==========================================
+ Coverage   64.72%   64.93%   +0.21%     
==========================================
  Files         425      424       -1     
  Lines       20672    20592      -80     
  Branches     2282     2280       -2     
==========================================
- Hits        13380    13372       -8     
+ Misses       7167     7097      -70     
+ Partials      125      123       -2

Impacted Files	Coverage Δ
superset/__init__.py	74.04% <0%> (-0.4%)	⬇️
superset/assets/src/syncBackend.js
superset/views/core.py	74.96% <0%> (+0.03%)	⬆️
superset/legacy.py	100% <0%> (+86.56%)	⬆️

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