Since go1.21, (*go/types.Checker).Files() has returned an error when a package has a GoVersion (specified in types.Config.GoVersion) that is newer than the go/types library it is compiled against. Error in question is:

	if check.version.after(version{1, goversion.Version}) {
		return fmt.Errorf("package requires newer Go version %v", check.version)
	}

x/tools/go/packages was assuming the only error not reported to types.Config.Error was types.errBadCgo. Example downstream issue: #65590.

This issue is to decide whether this error should be reported to the types.Config.Error field, and if so how?

@griesemer @adonovan