change error message to match VC-API spec

src/app.js

@@ -58,15 +58,11 @@ export async function build() {
         )
       }
       const verificationResult = await verifyCredential(vc)
-      console.log('verificationResult in app.js /credentials/verify:')
-      console.log(JSON.stringify(verificationResult))
+
       if (verificationResult.verified) {
         return res.json(verificationResult)
       } else {
-        throw new VerificationException(
-          400,
-          'A verifiableCredential property must be provided in the body and it must contain a verifiable credential.'
-        )
+        throw new VerificationException(400, 'invalid input!')
       }
     } catch (e) {
       // catch the async errors and pass them to the error logger and handler