[tests] Retain OutDir for ioslike tests

[mdh1418]

$(OutDir) was removed in the ioslike tests build for the purpose of saving space, however some projects that include references will need assemblies in the $(OutDir) directory for the CoreCompile target. In the libraries tests, there is a workaround for this. This PR examines whether or not the $(OutDir) needs to be removed, using a metric of <100MB remaining when it is not removed to determine that it should continue to be removed.

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Issue Details

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$(OutDir) was removed in the ioslike tests build for the purpose of saving space, however some projects that include references will need assemblies in the $(OutDir) directory for the CoreCompile target. In the libraries tests, there is a workaround for this. This PR examines whether or not the $(OutDir) needs to be removed, using a metric of <100MB remaining when it is not removed to determine that it should continue to be removed.

Author:	mdh1418
Assignees:	-
Labels:	area-Infrastructure-libraries
Milestone:	-

[mdh1418]

/azp run runtime-ioslike, runtime-maccatalyst

[azure-pipelines]

Azure Pipelines successfully started running 2 pipeline(s).

[mdh1418]

/azp run runtime-ioslike, runtime-maccatalyst

[azure-pipelines]

Azure Pipelines successfully started running 2 pipeline(s).

[mdh1418]

/azp run runtime-ioslike, runtime-maccatalyst

[azure-pipelines]

Azure Pipelines successfully started running 2 pipeline(s).

[mdh1418]

Filesystem       Size   Used  Avail Capacity iused      ifree %iused  Mounted on
/dev/disk1s1    380Gi  212Gi  152Gi    59% 5115518 3977424882    0%   /System/Volumes/Data

Across 6 runs of runtime-ioslike not from this PR, the average disk usage (Change in Avail Column between before build and after build)
tvOS: 12.166... Gi (56% -> 60% capacity)
iOS: 8 Gi (56% -> 58% capacity)

Across the 2 runs of runtime-ioslike from this PR, the average disk usage
tvOS: 42.5 Gi. (56% -> 68% capacity)
iOS: 9.5 Gi (56% -> 59% capacity)

tvOS lanes are impacted more because they build 197 workitems, whereas iOS lanes build just 4 workitems, so the tvOS capacity change is the metric to focus on.

[mdh1418]

/azp run runtime-ioslike, runtime-ioslikesimulator, runtime-maccatalyst

[azure-pipelines]

Azure Pipelines successfully started running 3 pipeline(s).

[mdh1418]

Looks like osx.1200.amd64.open has issues, will rerun the startuphook functional test again after the problem is resolved to verify that the original issue is resolved.

[mdh1418]

/azp run runtime-ioslike, runtime-ioslikesimulator, runtime-maccatalyst

[azure-pipelines]

Azure Pipelines successfully started running 3 pipeline(s).