s3api: return 403 AccessDenied when the request has no Date

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Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

weed/s3api/s3err/s3api_errors.go

@@ -569,7 +569,7 @@ var errorCodeResponse = map[ErrorCode]APIError{
 	ErrMissingDateHeader: {
 		Code:           "AccessDenied",
 		Description:    "AWS authentication requires a valid Date or x-amz-date header",
-		HTTPStatusCode: http.StatusBadRequest,
+		HTTPStatusCode: http.StatusForbidden,
 	},
 	ErrInvalidRequest: {
 		Code:           "InvalidRequest",