Failed to create closure from callable: class 'Http\HttplugBundle\Discovery \ConfiguredClientsStrategy' does not have a method 'onEvent'

After upgrade to symfony flex, i got this error after running php composer.phar install :

Failed to create closure from callable: class 'Http\HttplugBundle\Discovery \ConfiguredClientsStrategy' does not have a method 'onEvent'

on php 7.4 , ubuntu 16.04

php composer.phar show --latest 'sonata-project/*'
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sonata-project/admin-bundle              3.78.0 3.78.0 The missing Symfony Admin Generator
sonata-project/block-bundle              3.21.0 4.4.0  Symfony SonataBlockBundle
sonata-project/cache                     2.0.1  2.0.1  Cache library
sonata-project/cache-bundle              3.2.1  3.2.1  This bundle provides caching services
sonata-project/datagrid-bundle           2.5.0  3.2.0  Symfony SonataDatagridBundle
sonata-project/doctrine-extensions       1.10.1 1.10.1 Doctrine2 behavioral extensions
sonata-project/doctrine-orm-admin-bundle 3.24   3.24   Integrate Doctrine ORM into the SonataAdminBundle
sonata-project/easy-extends-bundle       2.5.0  2.5.0  Symfony SonataEasyExtendsBundle
sonata-project/exporter                  2.4.1  2.4.1  Lightweight Exporter library
sonata-project/form-extensions           1.6.0  1.6.0  Symfony form extensions
sonata-project/formatter-bundle          4.3.0  4.3.0  Symfony SonataFormatterBundle
sonata-project/google-authenticator      2.2.0  2.2.0  Library to integrate Google Authenticator into a PHP project
sonata-project/media-bundle              3.27.0 3.27.0 Symfony SonataMediaBundle
sonata-project/seo-bundle                2.12.0 2.12.0 Symfony SonataSeoBundle
sonata-project/timeline-bundle           3.6.0  3.6.0  Integrates SpyTimelineBundle into Sonata
sonata-project/twig-extensions           1.4.1  1.4.1  Sonata twig extensions
sonata-project/user-bundle               4.8.0  4.8.0  Symfony SonataUserBundle

here's my composer.json :

{
    "type": "project",
    "license": "proprietary",
    "require": {
        "php": "^7.1.3",
        "ext-ctype": "*",
        "ext-iconv": "*",
        "doctrine/annotations": "^1.10",
        "doctrine/doctrine-migrations-bundle": "2.2.x-dev",
        "friendsofsymfony/ckeditor-bundle": "^2.2",
        "friendsofsymfony/jsrouting-bundle": "^2.5",
        "friendsofsymfony/rest-bundle": "^2.7",
        "friendsofsymfony/user-bundle": "^2.1",
        "gedmo/doctrine-extensions": "^2.4",
        "hwi/oauth-bundle": "0.6.x-dev",
        "jms/i18n-routing-bundle": "^3.0",
        "jms/serializer-bundle": "^3.5",
        "jms/translation-bundle": "^1.4",
        "knplabs/knp-paginator-bundle": "^5.2",
        "knpuniversity/oauth2-client-bundle": "^2.0",
        "league/oauth2-google": "^3.0",
        "nelmio/api-doc-bundle": "^2.4",
        "php-http/guzzle6-adapter": "^1.1",
        "php-http/httplug-bundle": "^1.17",
        "samj/doctrine-sluggable-bundle": "^2.0",
        "sensio/framework-extra-bundle": "^5.5",
        "sonata-project/admin-bundle": "^3.56",
        "sonata-project/cache-bundle": "3.2.1",
        "sonata-project/datagrid-bundle": "^2.3",
        "sonata-project/doctrine-orm-admin-bundle": "^3.14",
        "sonata-project/formatter-bundle": "^4.1",
        "sonata-project/google-authenticator": "^2.2",
        "sonata-project/media-bundle": "^3.24",
        "sonata-project/seo-bundle": "^2.10",
        "sonata-project/timeline-bundle": "^3.5",
        "sonata-project/user-bundle": "^4.5",
        "stof/doctrine-extensions-bundle": "^1.3",
        "symfony-cmf/routing-bundle": "^2.3",
        "symfony/acl-bundle": "^2.0",
        "symfony/apache-pack": "^1.0",
        "symfony/console": "4.4.*",
        "symfony/dependency-injection": "4.4.*",
        "symfony/dotenv": "4.4.*",
        "symfony/flex": "^1.3.1",
        "symfony/framework-bundle": "4.4.*",
        "symfony/monolog-bundle": "^3.5",
        "symfony/orm-pack": "^1.0",
        "symfony/swiftmailer-bundle": "^3.4",
        "symfony/twig-bundle": "4.4.*",
        "symfony/twig-pack": "^1.0",
        "symfony/validator": "4.4.*",
        "symfony/webpack-encore-bundle": "^1.7",
        "symfony/yaml": "4.4.*",
        "twig/intl-extra": "^3.0",
        "twig/twig": "^2.10"
    },
    "require-dev": {
        "symfony/maker-bundle": "^1.14",
        "symfony/profiler-pack": "^1.0",
        "symfony/web-server-bundle": "4.4.*"
    },
    "config": {
        "disable-tls": true,
        "secure-http": false,
        "preferred-install": {
            "*": "dist"
        },
        "sort-packages": true
    },
    "autoload": {
        "psr-4": {
            "App\\": "src/"
        }
    },
    "autoload-dev": {
        "psr-4": {
            "App\\Tests\\": "tests/"
        }
    },
    "replace": {
        "paragonie/random_compat": "2.*",
        "symfony/polyfill-ctype": "*",
        "symfony/polyfill-iconv": "*",
        "symfony/polyfill-php71": "*",
        "symfony/polyfill-php70": "*",
        "symfony/polyfill-php56": "*"
    },
    "scripts": {
        "auto-scripts": {
            "cache:clear": "symfony-cmd",
            "assets:install %PUBLIC_DIR%": "symfony-cmd"
        },
        "post-install-cmd": [
            "@auto-scripts"
        ],
        "post-update-cmd": [
            "@auto-scripts"
        ]
    },
    "conflict": {
        "symfony/symfony": "*"
    }, 
    "extra": {
        "symfony": {
            "allow-contrib": false,
            "require": "4.4.*"
        }
    }
}

symfony / flex

Failed to create closure from callable: class 'Http\HttplugBundle\Discovery \ConfiguredClientsStrategy' does not have a method 'onEvent' #709