metropolis/node/core/curator: merge assignment into variable declaration

Change-Id: I85369786be45d732df26a7f5f5fd3e062f0e8146
Reviewed-on: https://review.monogon.dev/c/monogon/+/3004
Reviewed-by: Serge Bazanski <serge@monogon.tech>
Tested-by: Jenkins CI
diff --git a/metropolis/node/core/curator/impl_leader_test.go b/metropolis/node/core/curator/impl_leader_test.go
index 2d92536..f5072b6 100644
--- a/metropolis/node/core/curator/impl_leader_test.go
+++ b/metropolis/node/core/curator/impl_leader_test.go
@@ -1739,7 +1739,7 @@
 				eph.Close()
 			})
 
-			useTPM := false
+			var useTPM bool
 			if resR.TpmUsage == cpb.NodeTPMUsage_NODE_TPM_PRESENT_AND_USED {
 				useTPM = true
 			}