Correctly display the GCSettings specified in the runtimeconfig json via the GC Configuration API Call

[mrsharm]

Fixes #84198 by honoring the user specified GC Configuration by appropriately setting the Configuration obtained from both the Environment Variables and the JSON Configuration.

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Issue Details

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Fixes #84198 by honoring the user set GCHighMemPercent from the configuration.

Testing

Used the user's repro in the mentioned issue to confirm the issue is fixed. The output is:

ServerGC:True
ConcurrentGC:True
RetainVM:False
NoAffinitize:False
GCCpuGroup:False
GCLargePages:False
HeapCount:9
GCHeapAffinitizeMask:0
GCHeapAffinitizeRanges:
**GCHighMemPercent:75**
GCHeapHardLimit:209715201
GCHeapHardLimitPercent:0
GCHeapHardLimitSOH:0
GCHeapHardLimitLOH:0
GCHeapHardLimitPOH:0
GCHeapHardLimitSOHPercent:0
GCHeapHardLimitLOHPercent:0
GCHeapHardLimitPOHPercent:0
GCConserveMem:0
GCName:

Author:	mrsharm
Assignees:	-
Labels:	area-GC-coreclr
Milestone:	-

[mangod9]

are there any other settings which are not being reported?

[mrsharm]

are there any other settings which are not being reported?

Yes, working on a fix for them. The issue here is that there a few settings from the json configuration that aren't getting set properly because we aren't explicitly calling the equivalent Set{ConfigurationName} function. The settings are appropriately displayed if they are set as Environment Variables but seems like we didn't account for the case where they are applied from the JSON settings. To fix this, I am explicitly calling the corresponding Set method for each property.

Fixed the general case where we are setting the updated value that's meant to be displayed via the API to be set to the value obtained by the Environment Variable or JSON Configuration.

[cshung]

LGTM