I had a similar issue where I needed to test whether the correct cert was added to the Java keystore. This blog post by Matthew Davis shows a simple method for doing so. It does require access to a JDK.
Source: https://matthewdavis111.com/java/poke-ssl-test-java-certs/

Install JDK (if needed)

# Debian/Ubuntu
apt-get install -y default-jdk

# Rockylinux/Alma
dnf install -y java-latest-openjdk-devel

Source Code

Save the following to SSLPoke.java

import javax.net.ssl.SSLSocket;
import javax.net.ssl.SSLSocketFactory;
import java.io.*;

/** Establish a SSL connection to a host and port, writes a byte and
 * prints the response. See
 * http://confluence.atlassian.com/display/JIRA/Connecting+to+SSL+services
 */
public class SSLPoke {
    public static void main(String[] args) {
        if (args.length != 2) {
            System.out.println("Usage: "+SSLPoke.class.getName()+" <host> <port>");
            System.exit(1);
        }
        try {
            SSLSocketFactory sslsocketfactory = (SSLSocketFactory) SSLSocketFactory.getDefault();
            SSLSocket sslsocket = (SSLSocket) sslsocketfactory.createSocket(args[0], Integer.parseInt(args[1]));

            InputStream in = sslsocket.getInputStream();
            OutputStream out = sslsocket.getOutputStream();

            // Write a test byte to get a reaction :)
            out.write(1);

            while (in.available() > 0) {
                System.out.print(in.read());
            }
            System.out.println("Successfully connected");

        } catch (Exception exception) {
            exception.printStackTrace();
        }
    }
}

Compile the app

Run the following which will produce a Java class file SSLPoke.class

javac SSLPoke.java

Run the app

java SSLPoke <hostname> <port>
# e.g. java SSLPoke google.com 443

A message saying Successfully connected means the https connection is trusted, otherwise an exception will be printed.