fix: fix ES256K signature

Author: andreibogus

src/main/java/org/eclipse/tractusx/managedidentitywallets/service/JwtPresentationES256KService.java

@@ -177,6 +177,7 @@ public SignedJWT createSignedJwt(URI id, Did didIssuer, String audience, Seriali
     private static SignedJWT createSignedES256KJwt(ECPrivateKey ecPrivateKey, JWTClaimsSet claimsSet, String issuer) {
         try {
             JWSSigner signer = new ECDSASigner(ecPrivateKey);
+            signer.getJCAContext().setProvider(BouncyCastleProviderSingleton.getInstance());
             if (!signer.supportedJWSAlgorithms().contains(JWSAlgorithm.ES256K)) {
                 throw new UnsupportedAlgorithmException(String.format("Invalid signing method. Supported signing methods: %s",
                         signer.supportedJWSAlgorithms().stream().map(Algorithm::getName).collect(Collectors.joining(", "))));