chore(alerts): Remove activated alerts from rule endpoints

[ceorourke]

Another chunk of #81095 that removes the alert rule endpoint code for activated alerts.

This can't be merged until #81218 is merged.

Draft because removing this stuff from create_alert_rule breaks all tests that passed activation stuff. Might have to rethink this one.

[codecov]

❌ 71 Tests Failed:

Tests completed	Failed	Passed	Skipped
20737	71	20666	207

View the top 3 failed tests by shortest run time

tests.sentry.incidents.models.test_alert_rule.AlertRuleTest::test_conditionally_subscribing_project_initializes_activation

Stack Traces | 1.73s run time

#x1B[1m#x1B[.../incidents/models/test_alert_rule.py#x1B[0m:208: in test_conditionally_subscribing_project_initializes_activation
    assert len(created_subscriptions) == 1
#x1B[1m#x1B[31mE   assert 0 == 1#x1B[0m
#x1B[1m#x1B[31mE    +  where 0 = len([])#x1B[0m

tests.sentry.incidents.models.test_alert_rule.AlertRuleTest::test_subscribes_projects_to_alert_rule

Stack Traces | 1.81s run time

#x1B[1m#x1B[.../incidents/models/test_alert_rule.py#x1B[0m:155: in test_subscribes_projects_to_alert_rule
    assert mock_bulk_create_snuba_subscriptions.call_count == 0
#x1B[1m#x1B[31mE   AssertionError: assert 1 == 0#x1B[0m
#x1B[1m#x1B[31mE    +  where 1 = <MagicMock name='bulk_create_snuba_subscriptions' id='140632465841264'>.call_count#x1B[0m

tests.sentry.incidents.models.test_alert_rule.AlertRuleTest::test_conditionally_subscribe_project_to_alert_rules

Stack Traces | 1.85s run time

#x1B[1m#x1B[.../incidents/models/test_alert_rule.py#x1B[0m:183: in test_conditionally_subscribe_project_to_alert_rules
    assert len(created_subscriptions) == 1
#x1B[1m#x1B[31mE   assert 0 == 1#x1B[0m
#x1B[1m#x1B[31mE    +  where 0 = len([])#x1B[0m

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[getsantry]

This pull request has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you add the label WIP, I will leave it alone unless WIP is removed ... forever!

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"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀

[ceorourke]

don't close

[ceorourke]

Closing in favor of #83212