Derivation of stellar public key fails

[TheTrunk]

Describe the bug
Trying to get a public key from stellar secret key can throw an error in library

What version are you on?
Latest 8.1.1

To Reproduce
Simply try to generate many keypairs

const StellarSdk = require("stellar-sdk");

for (let i = 0; i < 1000; i++) {
  try {
    const pair = StellarSdk.Keypair.random();
    const sec = pair.secret();
    console.log(sec);
    const pub = pair.publicKey();
    console.log(pub);
  } catch (error) {
    console.log(error);
  }
}

You will encounter failiure approximantelly every 200th derivation.
Known private keys from which publicKey fails to derive

SDUYQO2PCSM7WUCX7SAFQOYGNGLNISPMILCHXQVPXVDFYYZ7LYTBPRXD
SB3M57ZLGRTL7PLBXS2BTBT3JLFEVMDTDUI3ERBCZBLF4GUIWLHEPAYC
SDNGQTMWIVCEISCYUWGBUFTKOB5MGEGGXGLKMXWDJADN5KQWSRMNGHDH
SDZIG2WTBW6AM7O6T7JYC6TVSBMMYH3I7DMUCTO5VXIHH45RDWKXVMIH

Expected behavior
Generation does not fail

Additional context

TypeError: medKey.ed25519 is not a function
    at Function.encodeEd25519PublicKey (C:\Users\User\Source\Repos\zelcore\node_modules\stellar-base\lib\strkey.js:73:51)
    at Keypair.publicKey (C:\Users\User\Source\Repos\zelcore\node_modules\stellar-base\lib\keypair.js:128:29)

[TheTrunk]

Version 8.0.0 and lower works well. Bug was introduced in v8.1.0 with the bump of major version of stellar-base

[Shaptic]

Thank you for bringing this to my attention! It's resolved by stellar/js-stellar-base#429 and will be included in base-5.2.1 and subsequently the pending sdk-8.2.0.

[Shaptic]

This should be closed as of v8.2.0!