SqlServerDsc: Add a new pipeline job to test SQL Server 2014 family

[SphenicPaul]

Details of the scenario you tried and the problem that is occurring

Suggestion to add another Azure Pipelines "job" within the build for the SqlServerDsc module to test the SQL Server 2014 family (e.g. SQL Server 2014 and Reporting Services 2014).

Verbose logs showing the problem

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Suggested solution to the issue

Add a new job to azure-pipelines.yml and update integration tests and unit tests to cater for the SQL2014, integration tests, and additional references to SQL Server version (e.g. 12 or 120) as appropriate.

Fix any resource issues that addition of tests for SQL2014 may identify.

See issue #1310 and PR #1676 (for example issue and resolution in respect of SQL2019).

The DSC configuration that is used to reproduce the issue (as detailed as possible)

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SQL Server edition and version the target node is running

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SQL Server PowerShell modules present on the target node

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The operating system the target node is running

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Version and build of PowerShell the target node is running

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Version of the DSC module that was used ('dev' if using current dev branch)

Dev