oeqa/gotoolchain: set GOPROXY

Since go-1.21 GOPROXY needs to be set explicitly, otherwise it fails with:
- GOPROXY list is not the empty string, but contains no entries

This fixes the selftest

(From OE-Core rev: c491d967858c01fead21495f44f1a9f8cdf8e833)

Signed-off-by: Jose Quaresma <jose.quaresma@foundries.io>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/lib/oeqa/selftest/cases/gotoolchain.py

@@ -54,6 +54,7 @@ class oeGoToolchainSelfTest(OESelftestTestCase):
         cmd = cmd + "export GOPATH=%s; " % self.go_path
         cmd = cmd + "export GOFLAGS=-modcacherw; "
         cmd = cmd + "export CGO_ENABLED=1; "
+        cmd = cmd + "export GOPROXY=https://proxy.golang.org,direct; "
         cmd = cmd + "${CROSS_COMPILE}go %s" % gocmd
         return runCmd(cmd).status