We have hardcoded Unix-style newlines in PluginInfo.toString. We should use `System.lineSeparator()` instead.
distribution/tools/plugin-cli/src/test/java/org/elasticsearch/plugins/cli/ListPluginsCommandTests.java
"version",
            "1.0",
            "elasticsearch.version",
            Version.CURRENT.toString(),
            "java.version",
            "1.8",
            "classname",
            classname,
            "has.native.controller",
            Boolean.toString(hasNativeController)
        );
    }
    public void testPluginsDirMissing() throws Exception {
        Files.delete(env.pluginsFile());
        IOException e = expectThrows(IOException.class, () -> execute());
        assertEquals("Plugins directory missing: " + env.pluginsFile(), e.getMessage());
    }
    public void testNoPlugins() throws Exception {
        execute();
        assertTrue(terminal.getOutput(), terminal.getOutput().isEmpty());
    }
    public void testOnePlugin() throws Exception {
        buildFakePlugin(env, "fake desc", "fake", "org.fake");
        execute();
        assertEquals(buildMultiline("fake"), terminal.getOutput());
    }
    public void testTwoPlugins() throws Exception {
        buildFakePlugin(env, "fake desc", "fake1", "org.fake");
        buildFakePlugin(env, "fake desc 2", "fake2", "org.fake");
        execute();