Don't require segwit in getblocktemplate for segwit signalling or mining

Segwit's version bit will be signalled for all invocations of CreateNewBlock,
and not specifying segwit only will cause CreateNewBlock to skip transactions
with witness from being selected.

src/versionbits.cpp

@@ -17,7 +17,7 @@ const struct BIP9DeploymentInfo VersionBitsDeploymentInfo[Consensus::MAX_VERSION
     },
     {
         /*.name =*/ "segwit",
-        /*.gbt_force =*/ false,
+        /*.gbt_force =*/ true,
     }
 };