fix: k6runner: add level=error to deferred log reporting code from runner

Author: nadiamoe

internal/k6runner/http_test.go

@@ -191,7 +191,7 @@ func TestScriptHTTPRun(t *testing.T) {
 			expectSuccess: false,
 			expectError:   ErrFromRunner,
 			expectLogs: nonDebugLogLine + fmt.Sprintf(
-				"msg=\"script did not execute successfully\" error=%q errorCode=%q\n",
+				"level=\"error\" msg=\"script did not execute successfully\" error=%q errorCode=%q\n",
 				"something went wrong",
 				"something-wrong",
 			),
@@ -209,7 +209,7 @@ func TestScriptHTTPRun(t *testing.T) {
 			expectSuccess: false,
 			expectError:   nil,
 			expectLogs: nonDebugLogLine + fmt.Sprintf(
-				"msg=\"script did not execute successfully\" error=%q errorCode=%q\n",
+				"level=\"error\" msg=\"script did not execute successfully\" error=%q errorCode=%q\n",
 				"syntax error somewhere or something",
 				"aborted",
 			),
@@ -226,7 +226,7 @@ func TestScriptHTTPRun(t *testing.T) {
 			expectSuccess: false,
 			expectErrorAs: &logfmt.SyntaxError{},
 			expectLogs: `level="error"` + "\n" + fmt.Sprintf(
-				"msg=\"script did not execute successfully\" error=%q errorCode=%q\n",
+				"level=\"error\" msg=\"script did not execute successfully\" error=%q errorCode=%q\n",
 				"we killed k6",
 				"aborted",
 			),
@@ -243,7 +243,7 @@ func TestScriptHTTPRun(t *testing.T) {
 			expectSuccess: false,
 			expectErrorAs: expfmt.ParseError{},
 			expectLogs: nonDebugLogLine + fmt.Sprintf(
-				"msg=\"script did not execute successfully\" error=%q errorCode=%q\n",
+				"level=\"error\" msg=\"script did not execute successfully\" error=%q errorCode=%q\n",
 				"we killed k6",
 				"aborted",
 			),

internal/k6runner/k6runner.go

@@ -151,7 +151,12 @@ func (r Processor) Run(ctx context.Context, registry *prometheus.Registry, logge
 	// other logs.
 	if result.ErrorCode != "" {
 		defer func() {
-			err := logger.Log("msg", "script did not execute successfully", "error", result.Error, "errorCode", result.ErrorCode)
+			err := logger.Log(
+				"level", "error",
+				"msg", "script did not execute successfully",
+				"error", result.Error,
+				"errorCode", result.ErrorCode,
+			)
 			if err != nil {
 				internalLogger.Error().
 					Err(err).