fix(examples): update /r/demo/bar20/gno.mod (#2398)

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- [ ] Added new tests, or not needed, or not feasible
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Update /r/demo/bar20/gno.mod because of failing pipeline

examples/gno.land/r/demo/bar20/gno.mod

@@ -1,4 +1,4 @@
-module bar20
+module gno.land/r/demo/bar20
 
 require (
 	gno.land/p/demo/grc/grc20 v0.0.0-latest