chore: finish drop columns migrations (#5280)

# What this PR does

Second, and final part of, #5277

## Checklist

- [x] Unit, integration, and e2e (if applicable) tests updated
- [x] Documentation added (or `pr:no public docs` PR label added if not
required)
- [x] Added the relevant release notes label (see labels prefixed w/
`release:`). These labels dictate how your PR will
    show up in the autogenerated release notes.

engine/apps/alerts/migrations/0069_remove_channelfilter__slack_channel_id_db.py

@@ -0,0 +1,21 @@
+# Generated by Django 4.2.16 on 2024-11-20 20:21
+
+import common.migrations.remove_field
+import django_migration_linter as linter
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('alerts', '0068_remove_resolutionnoteslackmessage__slack_channel_id_state'),
+    ]
+
+    operations = [
+        linter.IgnoreMigration(),
+        common.migrations.remove_field.RemoveFieldDB(
+            model_name='channelfilter',
+            name='_slack_channel_id',
+            remove_state_migration=('alerts', '0067_remove_channelfilter__slack_channel_id_state'),
+        ),
+    ]

engine/apps/alerts/migrations/0070_remove_resolutionnoteslackmessage__slack_channel_id_db.py

@@ -0,0 +1,21 @@
+# Generated by Django 4.2.16 on 2024-11-20 20:23
+
+import common.migrations.remove_field
+import django_migration_linter as linter
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('alerts', '0069_remove_channelfilter__slack_channel_id_db'),
+    ]
+
+    operations = [
+        linter.IgnoreMigration(),
+        common.migrations.remove_field.RemoveFieldDB(
+            model_name='resolutionnoteslackmessage',
+            name='_slack_channel_id',
+            remove_state_migration=('alerts', '0068_remove_resolutionnoteslackmessage__slack_channel_id_state'),
+        ),
+    ]

engine/apps/schedules/migrations/0021_remove_oncallschedule_channel_db.py

@@ -0,0 +1,21 @@
+# Generated by Django 4.2.16 on 2024-11-20 20:12
+
+import common.migrations.remove_field
+import django_migration_linter as linter
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('schedules', '0020_remove_oncallschedule_channel_state'),
+    ]
+
+    operations = [
+        linter.IgnoreMigration(),
+        common.migrations.remove_field.RemoveFieldDB(
+            model_name='oncallschedule',
+            name='channel',
+            remove_state_migration=('schedules', '0020_remove_oncallschedule_channel_state'),
+        ),
+    ]

engine/apps/user_management/migrations/0029_remove_organization_general_log_channel_id_db.py

@@ -0,0 +1,21 @@
+# Generated by Django 4.2.16 on 2024-11-20 17:58
+
+import common.migrations.remove_field
+import django_migration_linter as linter
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('user_management', '0028_remove_organization_general_log_channel_id_state'),
+    ]
+
+    operations = [
+        linter.IgnoreMigration(),
+        common.migrations.remove_field.RemoveFieldDB(
+            model_name='organization',
+            name='general_log_channel_id',
+            remove_state_migration=('user_management', '0028_remove_organization_general_log_channel_id_state'),
+        ),
+    ]