Add coaps support based on java-coap and bouncy castle at client side

[sbernard31]

This PR aims to add support of CoAP over DTLS based on java-coap and Bouncy Castle at client side.

Here some limitations from bouncy castle :

1. There is no async API.
2. Client API seem to not support DTLS Role Exchange. (but it should be implemented using client and server api)
3. API is very low level some and doesn't reuse JSSE class (like PublicKey, PrivateKey, Certificate ...) from openJDK

Some missing task :

• ✔️ add some unit test about equals/hashcode
• 📆 check if we need to implement getTransportContext() (post pone)
• ✔️ clean sonard issues

I also modify LeshanClientDemo so when --use-java-coap is used, this will now use java-coap for coaps too. (before it was only for coap)

[sonarqubecloud]

Quality Gate passed

Issues
2 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.1% Duplication on New Code

See analysis details on SonarQube Cloud

[sonarqubecloud]

Quality Gate passed

Issues
2 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.1% Duplication on New Code

See analysis details on SonarQube Cloud