Fix race condition when running mssql tests
diff --git a/scripts/ci/docker-compose/backend-mssql.yml b/scripts/ci/docker-compose/backend-mssql.yml
index 69b4aa5fb6e5a..7fc5540e467a0 100644
--- a/scripts/ci/docker-compose/backend-mssql.yml
+++ b/scripts/ci/docker-compose/backend-mssql.yml
@@ -49,6 +49,12 @@ services:
     entrypoint:
       - bash
       - -c
-      - opt/mssql-tools/bin/sqlcmd -S mssql -U sa -P Airflow123 -i /mssql_create_airflow_db.sql || true
+      - >
+        for i in {1..10};
+        do
+            /opt/mssql-tools/bin/sqlcmd -S mssql -U sa -P Airflow123 -i /mssql_create_airflow_db.sql &&
+                exit 0;
+            sleep 1;
+        done
     volumes:
       - ./mssql_create_airflow_db.sql:/mssql_create_airflow_db.sql:ro

There is a race condition where initialization of Airlfow DB
for mssql might be executed when the server is started but it is
not yet initialized with a model db needed to create airflow db.

In such case mssql database intialization will fail as it will
not be able to obtain a locl on the `model` database. The error
in the mssqlsetup container will be similar to:

```
Msg 1807, Level 16, State 3, Server d2888dd467fe, Line 20
Could not obtain exclusive lock on database 'model'. Retry the operation later.
Msg 1802, Level 16, State 4, Server d2888dd467fe, Line 20
CREATE DATABASE failed. Some file names listed could not be created. Check related errors.
Msg 5011, Level 14, State 5, Server d2888dd467fe, Line 21
User does not have permission to alter database 'airflow', the database does not exist, or the database is not in a state that allows access checks.
Msg 5069, Level 16, State 1, Server d2888dd467fe, Line 21
ALTER DATABASE statement failed.
```

This PR alters the setup job to try to create airflow db
several times and wait a second before every retry.

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