@Test
    public void testGetPluginPathByPluginExt() {
        System.setProperty("plugin-ext", "/testUrl");
        File jarFile = ShenyuPluginPathBuilder.getPluginFile("");
        assertNotNull(jarFile);
    }
test  for plugin-ext.
-Dplugin-ext=D:\testUrl
shenyu-web/src/test/java/org/apache/shenyu/web/loader/ShenyuPluginPathBuilderTest.java