chore: update output format in golangci-lint config and improve response handling in tests

.golangci.yml

@@ -9,4 +9,5 @@ run:
   timeout: 5m
 
 output:
-  format: colored-line-number
+  formats:
+    - colored-line-number

device_certificates_test.go

@@ -177,7 +177,7 @@ func newMockDeviceCertificatesServer() *httptest.Server {
 </SOAP-ENV:Envelope>`
 		}
 
-		w.Write([]byte(response))
+		_, _ = w.Write([]byte(response))
 	}))
 }
 

device_wifi_test.go

@@ -144,7 +144,7 @@ func newMockDeviceWiFiServer() *httptest.Server {
 </SOAP-ENV:Envelope>`
 		}
 
-		w.Write([]byte(response))
+		_, _ = w.Write([]byte(response))
 	}))
 }