[DS][7/n] Create MaterializedSchedulingCondition

[OwenKephart]

Summary & Motivation

Creates a simple MaterializedSchedulingCondition and a base class StatusSchedulingCondition.

The StatusSchedulingCondition class is there to make future implementations of things like "InProgressSchedulingCondition` simpler

How I Tested These Changes

[OwenKephart]

• #21511 : 2 dependent PRs (#21512 , #21520 )
• #21510
• #21508
• #21507
• #21505 👈
• #21504
• #21503
• #21502
• #21501
• #21500
• #21499
• master

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[OwenKephart]

Merge activity

• May 3, 5:31 PM EDT: @OwenKephart started a stack merge that includes this pull request via Graphite.
• May 3, 5:44 PM EDT: Graphite rebased this pull request as part of a merge.
• May 3, 5:45 PM EDT: @OwenKephart merged this pull request with Graphite.