ref(alerts): Pass org instead of rule

[ceorourke]

We only ever use alert_rule.organization here so we can just pass the organization instead of the alert rule. As I'm writing the migration spec for ACI I noticed this and wanted to remove the reference to alert rule.

[codecov]

Codecov Report

Attention: Patch coverage is 25.00000% with 6 lines in your changes missing coverage. Please review.

✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
...seer/anomaly_detection/get_historical_anomalies.py	0.00%	2 Missing and 1 partial ⚠️
src/sentry/seer/anomaly_detection/store_data.py	0.00%	1 Missing and 1 partial ⚠️
src/sentry/seer/anomaly_detection/utils.py	66.66%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@           Coverage Diff            @@
##           master   #79236    +/-   ##
========================================
  Coverage   78.33%   78.33%            
========================================
  Files        7123     7125     +2     
  Lines      314393   314499   +106     
  Branches    51345    51366    +21     
========================================
+ Hits       246274   246361    +87     
- Misses      61674    61679     +5     
- Partials     6445     6459    +14     

[saponifi3d]

really like this change - agree it will help simplify migration work with ACI too 🎉