Add Auth support for websocket clients

[Bhashinee]

This task has the following auth types to be completed.
This is implemented in a declarative manner.

• Bearer token

webscket:Client wsClient = check new("ws://localhost:21324/bearerToken/", config = {
            auth: {
              token: "JlbmMiOiJBMTI4Q0JDLUhTMjU2Inikn"
            }
        });

• Basic auth

websocket:Client wsClient = check new("ws://localhost:21318/basicAuth/", config = {
            auth: {
                username: "alice2",
                password: "1234"
            }
        });

• JWT

websocket:Client wsClient = check new("ws://localhost:21320/jwtSyncAuthService/", config = {
            auth: {
                    username: "wso2",
                    issuer: "ballerina",
                    audience: ["ballerina", "ballerina.org", "ballerina.io"],
                    keyId: "5a0b754-895f-4279-8843-b745e11a57e9",
                    customClaims: { "scp": "hello" },
                    expTime: 3600,
                    signatureConfig: {
                        config: {
                            keyAlias: "ballerina",
                            keyPassword: "ballerina",
                            keyStore: {
                                path: "tests/certsAndKeys/ballerinaKeystore.p12",
                                password: "ballerina"
                            }
                        }
                    }
                }
            });

• OAuth2

websocket:OAuth2DirectTokenConfig config = {
    refreshUrl: "https://localhost:9401/oauth2/token/refresh",
    refreshToken: "XlfBs91yquexJqDaKEMzVg==",
    clientId: "3MVG9YDQS5WtC11paU2WcQjBB3L5w4gz52uriT8ksZ3nUVjKvrfQMrU4uvZohTftxStwNEW4cfStBEGRxRL68",
    clientSecret: "9205371918321623741",
    scopes: ["token-scope1", "token-scope2"],
    clientConfig: {
        secureSocket: {
           cert: {
               path: "tests/certsAndKeys/ballerinaTruststore.p12",
               password: "ballerina"
           }
        }
    }
};

websocket:Client wsClient = check new("ws://localhost:21325/oauthService/", config = {auth: config});