syntax error in ettus_rfnoc_graph.block.yml

[jpalladino]

Line 25 of ettus_rfnoc_graph.block.yml in the maint-3.8-uhd4.0 branch (and possibly others) looks like:
self.rfnoc_graph = ${id} = ettus.rfnoc_graph(uhd.device_addr("${graph_args}")))
You can see there are 2 open parentheses and 3 close parentheses. This leads to syntax errors when running a flowgraph including the RFNoC Graph block. Removing the extra close parenthesis fixes it.