Add missing migration for akslot field update

Verbose name of AKSlot.fixed was updated in a previous commit, this migration reflects this change

AKModel/migrations/0043_akslot_fixed_improve_verbose_name.py

+# Generated by Django 3.1.5 on 2021-01-29 15:43
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('AKModel', '0042_akslot_fixed'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='akslot',
+            name='fixed',
+            field=models.BooleanField(default=False, help_text='Length and time of this AK should not be changed', verbose_name='Scheduling fixed'),
+        ),
+    ]