daemon/logger/splunk: use constants for http methods

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

daemon/logger/splunk/splunk.go

@@ -495,7 +495,7 @@ func (l *splunkLogger) tryPostMessages(ctx context.Context, messages []*splunkMe
 			return err
 		}
 	}
-	req, err := http.NewRequest("POST", l.url, bytes.NewBuffer(buffer.Bytes()))
+	req, err := http.NewRequest(http.MethodPost, l.url, bytes.NewBuffer(buffer.Bytes()))
 	if err != nil {
 		return err
 	}

daemon/logger/splunk/splunk_test.go

@@ -105,7 +105,7 @@ func TestNewWithProxy(t *testing.T) {
 	proxyFunc := splunkLogger.transport.Proxy
 	assert.Assert(t, proxyFunc != nil)
 
-	req, err := http.NewRequest("GET", splunkURL, nil)
+	req, err := http.NewRequest(http.MethodGet, splunkURL, nil)
 	assert.NilError(t, err)
 
 	proxyURL, err := proxyFunc(req)