fix(ci): update trunk go runtime and format test files

- Update trunk go runtime from 1.24.3 to 1.25.6 to match go.mod
- Fix trailing newline formatting in label test files

Author: mlwelles

.trunk/trunk.yaml

@@ -14,7 +14,7 @@ plugins:
 # Many linters and tools depend on runtimes - configure them here. (https://docs.trunk.io/runtimes)
 runtimes:
   enabled:
-    - go@1.24.3
+    - go@1.25.6
     - [email protected]
     - [email protected]
 

systest/label/docker-compose.yml

@@ -70,4 +70,4 @@ services:
     command:
       /gobin/dgraph ${COVERAGE_OUTPUT} zero --telemetry "reports=false;" --raft="idx=1;"
       --my=zero1:5080 --replicas=1 --logtostderr -v=2 --bindall
-volumes: {}
+volumes: {}

systest/label/label_test.go

@@ -389,4 +389,4 @@ func TestMissingLabelGroupError(t *testing.T) {
 	require.Contains(t, err.Error(), "nonexistent_label",
 		"error should mention the missing label")
 	t.Log("Verified: non-existent label produces correct error!")
-}
+}