fix(deps): elliptic upgrade to >6.5.3 for CVE-2020-28498

The updates here were automatically done by running the
`npx lerna-audit` shell command in the project root.

GHSA-r9p9-mrjm-926w

CVE-2020-28498
moderate severity
Vulnerable versions: < 6.5.4
Patched version: 6.5.4
The npm package elliptic before version 6.5.4 are vulnerable to Cryptographic Issues via the secp256k1 implementation in elliptic/ec/key.js. There is no check to confirm that the public key point passed into the derive function actually exists on the secp256k1 curve. This results in the potential for the private key used in this implementation to be revealed after a number of ECDH operations are performed.

Signed-off-by: Peter Somogyvari <peter.somogyvari@accenture.com>