Disable mssql linux test pipeline (#2076)

## Why make this change?

- Closes #2077 While we investigate #2010 , disabling MSSQL linux tests
to allow us to be productive while solution is found.

## What is this change?

- Sets Linux MSSQL test job condition to false to disable job. The
intent is to keep the pipeline config without deleting and have a simple
re-enable task when appropriate.
- Solution credit:
https://developercommunity.visualstudio.com/t/add-support-to-temporarily-disableskip-a-job-in-mu/393253

## How was this tested?

- [x] Integration Tests
Shows as skipped as intended:

![image](https://github.com/Azure/data-api-builder/assets/6414189/13dd6325-d120-4d9f-bdb5-8cc12dbed4b0)

.pipelines/mssql-pipelines.yml

@@ -18,6 +18,7 @@ trigger:
 
 jobs:
 - job: linux
+  condition: false # Disable until we resolve flakey pipeline issue. https://github.com/Azure/data-api-builder/issues/2010
   pool:
     vmImage: 'ubuntu-latest'
   variables: