Propose to remove set-platform-properties

System tests are running through TKG. Using set-platform-properties in system tests to set all properties (i.e., platform, osname, arc, bits, etc) again is unnecessary and often requires additional maintenance (For example: https://github.com/eclipse-openj9/openj9/issues/18110)

https://github.com/adoptium/STF/blob/f8d647e99075e77511c00df826c6dfe362bb928e/stf.build/include/top.xml#L480-L522

I would like to propose to remove it. Unfortunately, this will not be a simple deletion. We will need to ensure all properties are set properly.

Start with the set-platform-properties definition in stf.build/include/top.xml, lines 480-522, and review how system tests run through TKG. Trace which platform, osname, arc, bits, and other properties are currently supplied, then verify that all required properties remain set after removing the mechanism.

Written by the indexing model from the issue text.