[🚀 Feature]: webdriver connect pool maxsize increase

[Liu-XinYuan]

Feature and motivation

When I am doing automated testing, I need to asynchronously monitor whether the verification code pop-up box appears. At this time, because the default connection pool size is 1, performance queue and log warnings appear.
[Warning] The connection pool is full and connections are being dropped: xxxx. Connection pool size: 1

Usage example

Asynchronously monitor pop-up boxes that appear randomly

[github-actions]

@Liu-XinYuan, thank you for creating this issue. We will troubleshoot it as soon as we can.

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Thank you!

[Liu-XinYuan]

The code involved is as follows：
class RemoteConnection

def _get_connection_manager(self):
    pool_manager_init_args = {"timeout": self.get_timeout()}
    if self._ca_certs:
        pool_manager_init_args["cert_reqs"] = "CERT_REQUIRED"
        pool_manager_init_args["ca_certs"] = self._ca_certs

    if self._proxy_url:
        if self._proxy_url.lower().startswith("sock"):
            from urllib3.contrib.socks import SOCKSProxyManager

            return SOCKSProxyManager(self._proxy_url, **pool_manager_init_args)
        if self._identify_http_proxy_auth():
            self._proxy_url, self._basic_proxy_auth = self._separate_http_proxy_auth()
            pool_manager_init_args["proxy_headers"] = urllib3.make_headers(proxy_basic_auth=self._basic_proxy_auth)
        return urllib3.ProxyManager(self._proxy_url, **pool_manager_init_args)

    return urllib3.PoolManager(**pool_manager_init_args)``