switch to a mostly working test sqlserver

The standard mssql server image does not work on ARM [1].

Instead, we use `azure-sql-edge` [2], which provides a sufficient subset
of mssql server API to test most of our integration.

Unfortunately, this image does not support stored procedures [3], so
tests related to these will still fail locally.

[1] microsoft/mssql-docker#668
[2] https://hub.docker.com/_/microsoft-azure-sql-edge
[3] https://learn.microsoft.com/en-us/azure/azure-sql-edge/features#unsupported-features

docker-compose.yml

@@ -12,7 +12,10 @@ services:
     ports:
       - "127.0.0.1:5432:5432"
   mssql:
-    image: mcr.microsoft.com/mssql/server:2017-latest-ubuntu
+  # A working MSSQL server is not available on ARM.
+  # This image provides _most_ of sqlserver functionalities, but
+  # does not support stored procedures (corresponding tests will fail)
+    image: mcr.microsoft.com/mssql/azure-sql-edge
     environment:
       - "ACCEPT_EULA=Y"
       - "SA_PASSWORD=DD_HUNTER2"