fix: packages/instant/package.json to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-ELLIPTIC-8172694
- https://snyk.io/vuln/SNYK-JS-ELLIPTIC-8187303

packages/instant/package.json

@@ -44,10 +44,10 @@
     "homepage": "https://github.com/0xProject/0x-monorepo/packages/instant/README.md",
     "dependencies": {
         "@0x/assert": "^3.0.9",
-        "@0x/asset-swapper": "^4.6.0",
+        "@0x/asset-swapper": "^16.66.4",
         "@0x/contract-wrappers": "^13.8.0",
         "@0x/json-schemas": "^5.1.0",
-        "@0x/subproviders": "^6.1.1",
+        "@0x/subproviders": "^7.0.0",
         "@0x/utils": "^5.5.1",
         "@0x/web3-wrapper": "^7.2.0",
         "babel-runtime": "^6.26.0",