pass context to bundler in hotswapper

Author: mshabarov

flow-server/src/main/java/com/vaadin/flow/component/internal/StyleSheetHotswapper.java

@@ -567,8 +567,20 @@ private Optional<String> tryBundlePublicStylesheet(
 
             for (File stylesheet : stylesheets) {
                 try {
+                    String contextPath = "";
+                    if (service
+                            .getContext() instanceof com.vaadin.flow.server.VaadinServletContext) {
+                        try {
+                            contextPath = ((com.vaadin.flow.server.VaadinServletContext) service
+                                    .getContext()).getContext()
+                                    .getContextPath();
+                        } catch (Exception ignore) {
+                            contextPath = "";
+                        }
+                    }
                     String bundled = CssBundler.inlineImportsForPublicResources(
-                            stylesheet.getParentFile(), stylesheet);
+                            stylesheet.getParentFile(), stylesheet, true,
+                            contextPath);
                     return Optional.ofNullable(bundled);
                 } catch (IOException ioe) {
                     LOGGER.debug("Failed to inline CSS imports for {}",