fix: -broadcast true in doc (gnolang#1288)

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- [ ] Added new tests, or not needed, or not feasible
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examples/gno.land/r/demo/groups/README.md

@@ -8,7 +8,7 @@
 
 ### - create group
 
-    ./build/gnokey maketx call -func "CreateGroup" -args "dao_trinity_ngo" -gas-fee "1000000ugnot" -gas-wanted 4000000 -broadcast true -chainid dev -remote 0.0.0.0:26657 -pkgpath "gno.land/r/demo/groups" test1 
+    ./build/gnokey maketx call -func "CreateGroup" -args "dao_trinity_ngo" -gas-fee "1000000ugnot" -gas-wanted 4000000 -broadcast -chainid dev -remote 0.0.0.0:26657 -pkgpath "gno.land/r/demo/groups" test1 
 
 ### - add member