fix(package): update cids to version 0.7.0

BREAKING CHANGE: Returned v1 CIDs now default to base32 encoding

Previous versions returned a base58 encoded string when `toString()`/
`toBaseEncodedString()` was called on a CIDv1. It now returns a base32
encoded string.

package.json

@@ -33,7 +33,7 @@
   },
   "homepage": "https://github.com/ipld/js-ipld-zcash#readme",
   "dependencies": {
-    "cids": "~0.6.0",
+    "cids": "~0.7.0",
     "multicodec": "~0.5.1",
     "multihashes": "~0.4.12",
     "multihashing-async": "~0.7.0",