GbXMLReverseTranslator schema validation using wrong schema version

[macumber]

Issue overview

The GbXMLReverseTranslator performs a schema validation using GreenBuildingXML_Ver7.03.xsd no matter which version of gbXML is being translated. This gives false errors about gbXML files being invalid when translating gbXML files which are valid against older gbXML schema versions. This includes some of the test files such as
https://github.com/NREL/OpenStudio/blob/develop/resources/gbxml/gbXMLStandard_Single_Family_Residential_2016.xml

Current Behavior

This line always validates the gbXML being translated against the GreenBuildingXML_Ver7.03.xsd

https://github.com/NREL/OpenStudio/blob/develop/src/utilities/xml/XMLValidator.cpp#L480

Expected Behavior

The gbXML should be validated against whichever version of the gbXML schema it references using the version attribute https://www.ivoa.net/documents/Notes/XMLVers/20180529/EN-schemaVersioning-1.0-20180529.html#tth_sEc2.2.1

Steps to Reproduce

require 'openstudio'

file = "gbXMLStandard_Single_Family_Residential_2016.xml"

# translate the model
# this will print out incorrect XMLValidator errors/warnings as well as GbXMLReverseTranslator errors/warnings
rt = OpenStudio::GbXML::GbXMLReverseTranslator.new
model = rt.loadModel(file)
#puts model.get
model.get.save("translated.osm", true)

Possible Solution

Include copies of all the gbXML schema files and select the correct one based on the xml version attribute.

Even better would be to implement some sort of version translator for gbXML files. However, this would clearly be an enhancement vs a bug fix.

Details

Environment

Some additional details about your environment for this issue (if relevant):

• Platform (Operating system, version):
• Version of OpenStudio (if using an intermediate build, include SHA):

Context

It is confusing to see messages saying that a gbXML file is not valid against the schema when it actually is (when compared to the correct version of the schema).

[jmarrec]

The RT rules are written to target the gbxml schema Version 7.03 - August 2023.

There is absolutely no guarantee being given that we support files created with an older schema.

Maybe we could actually look for that version attribute and give a clearer warning though.