[release/9.0-preview7] Don't enable validation when UseDefaultServiceProvider is called #105356
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Backport of #105170 to release/9.0-preview7
/cc @ericstj
Customer Impact
UseDefaultServiceProvider Is ignored. #99199 intentionally established new defaults for
ServiceProviderOptionsin development environment. However it did not honor changes made toServiceProviderOptionswithUseDefaultServiceProvider. This can cause applications to fail calls toHostBuilder.Build()as they will now be doing new validation.This regression was found in App Compat testing.
Regression
#99199
Testing
App testing to verify fix. Unit tests added.
Risk
Low. This change makes a previous change less breaking. The original change is still breaking but this helps us better understand if that's too breaking and needs to be reverted completely or not.