fix: add missing @digitalbazaar/ezcap-express to dependencies

Author: bparth24

package.json

@@ -31,6 +31,7 @@
   "dependencies": {
     "@digitalbazaar/ed25519-signature-2020": "^5.4.0",
     "@digitalbazaar/ezcap": "^4.1.0",
+    "@digitalbazaar/ezcap-express": "^7.2.0",
     "@digitalbazaar/http-client": "^4.2.0",
     "@digitalbazaar/lru-memoize": "^4.0.0",
     "@digitalbazaar/zcap": "^9.0.1",