Don't always build source build with ci flag

[MichaelSimons]

Local dev builds should not normally be building source-build with the "ci" flag. The official builds/ci will set this appropriately. This change removes the "ci" flags for source-build.

[ghost]

I couldn't figure out the best area label to add to this PR. If you have write-permissions please help me learn by adding exactly one area label.

[ViktorHofer]

You will need to port these changes back into main as well. Same for the portable change that @dseefeld merged yesterday.

[ViktorHofer]

@danmoseley should we treat source build work as tell-mode?

[danmoseley]

@danmoseley should we treat source build work as tell-mode?

In my mind - yes. This counts as "Infrastructure work necessary to ship". cc @jeffschwMSFT in case he differs.

[ghost]

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Issue Details

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Local dev builds should not normally be building source-build with the "ci" flag. The official builds/ci will set this appropriately. This change removes the "ci" flags for source-build.

Author:	MichaelSimons
Assignees:	dseefeld, ViktorHofer, crummel
Labels:	area-Infrastructure
Milestone:	-

[MichaelSimons]

@ViktorHofer - Has all criteria been satisfied? If so please merge.