Replace 'every' occurence of vc_jwt with jwt_vc

[georgepadayatti]

This has to be changed in the following places:

1. Issuer well-known configuration: https://github.com/EWC-consortium/ewc-wallet-conformance-backend/blob/main/data/issuer-config.json
2. Credential endpoint:

   ewc-wallet-conformance-backend/routes/routes.js

   Lines 220 to 223 in b429a16

   	// console.log(credential);
   	if (format === "jwt_vc") {
   	let payload = {};
   	if (requestedCredentials != null && requestedCredentials[0] === "PID") {

[endimion]

fixed by last merge