Update elliptic for Improper Verification of Cryptographic Signature (h…

…ttps://security.snyk.io/vuln/SNYK-JS-ELLIPTIC-8187303)

package.json

@@ -1,6 +1,6 @@
 {
 	"name": "browserify-sign",
-	"version": "4.2.3",
+	"version": "4.2.4",
 	"description": "adds node crypto signing for browsers",
 	"bugs": {
 		"url": "https://github.com/crypto-browserify/browserify-sign/issues"
@@ -33,7 +33,7 @@
 		"browserify-rsa": "^4.1.0",
 		"create-hash": "^1.2.0",
 		"create-hmac": "^1.1.7",
-		"elliptic": "^6.5.5",
+		"elliptic": "^6.6.1",
 		"hash-base": "~3.0",
 		"inherits": "^2.0.4",
 		"parse-asn1": "^5.1.7",