handle if webcrypto private key is empty or empty object

[hcote]

📦 Pull Request

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✅ Fixed Issues

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📦 Published PR as canary version: Canary Versions

:sparkles: Test out this PR locally via: ```bash npm install @magic-ext/algorand@16.5.1-canary.696.7468151309.0 npm install @magic-ext/aptos@4.5.1-canary.696.7468151309.0 npm install @magic-ext/avalanche@16.5.1-canary.696.7468151309.0 npm install @magic-ext/bitcoin@16.5.1-canary.696.7468151309.0 npm install @magic-ext/conflux@14.5.1-canary.696.7468151309.0 npm install @magic-ext/cosmos@16.5.1-canary.696.7468151309.0 npm install @magic-ext/ed25519@12.5.1-canary.696.7468151309.0 npm install @magic-ext/flow@16.5.1-canary.696.7468151309.0 npm install @magic-ext/gdkms@4.5.1-canary.696.7468151309.0 npm install @magic-ext/harmony@16.5.1-canary.696.7468151309.0 npm install @magic-ext/icon@16.5.1-canary.696.7468151309.0 npm install @magic-ext/near@16.5.1-canary.696.7468151309.0 npm install @magic-ext/oauth@15.6.1-canary.696.7468151309.0 npm install @magic-ext/oidc@4.5.1-canary.696.7468151309.0 npm install @magic-ext/polkadot@16.5.1-canary.696.7468151309.0 npm install @magic-ext/react-native-bare-oauth@18.2.1-canary.696.7468151309.0 npm install @magic-ext/react-native-expo-oauth@18.2.1-canary.696.7468151309.0 npm install @magic-ext/solana@18.4.1-canary.696.7468151309.0 npm install @magic-ext/taquito@13.5.1-canary.696.7468151309.0 npm install @magic-ext/terra@13.5.1-canary.696.7468151309.0 npm install @magic-ext/tezos@16.5.1-canary.696.7468151309.0 npm install @magic-ext/webauthn@15.5.1-canary.696.7468151309.0 npm install @magic-ext/zilliqa@16.5.1-canary.696.7468151309.0 npm install @magic-sdk/commons@17.5.1-canary.696.7468151309.0 npm install @magic-sdk/pnp@15.6.1-canary.696.7468151309.0 npm install @magic-sdk/provider@21.5.1-canary.696.7468151309.0 npm install @magic-sdk/react-native-bare@22.5.1-canary.696.7468151309.0 npm install @magic-sdk/react-native-expo@22.5.1-canary.696.7468151309.0 npm install magic-sdk@21.5.1-canary.696.7468151309.0 # or yarn add @magic-ext/algorand@16.5.1-canary.696.7468151309.0 yarn add @magic-ext/aptos@4.5.1-canary.696.7468151309.0 yarn add @magic-ext/avalanche@16.5.1-canary.696.7468151309.0 yarn add @magic-ext/bitcoin@16.5.1-canary.696.7468151309.0 yarn add @magic-ext/conflux@14.5.1-canary.696.7468151309.0 yarn add @magic-ext/cosmos@16.5.1-canary.696.7468151309.0 yarn add @magic-ext/ed25519@12.5.1-canary.696.7468151309.0 yarn add @magic-ext/flow@16.5.1-canary.696.7468151309.0 yarn add @magic-ext/gdkms@4.5.1-canary.696.7468151309.0 yarn add @magic-ext/harmony@16.5.1-canary.696.7468151309.0 yarn add @magic-ext/icon@16.5.1-canary.696.7468151309.0 yarn add @magic-ext/near@16.5.1-canary.696.7468151309.0 yarn add @magic-ext/oauth@15.6.1-canary.696.7468151309.0 yarn add @magic-ext/oidc@4.5.1-canary.696.7468151309.0 yarn add @magic-ext/polkadot@16.5.1-canary.696.7468151309.0 yarn add @magic-ext/react-native-bare-oauth@18.2.1-canary.696.7468151309.0 yarn add @magic-ext/react-native-expo-oauth@18.2.1-canary.696.7468151309.0 yarn add @magic-ext/solana@18.4.1-canary.696.7468151309.0 yarn add @magic-ext/taquito@13.5.1-canary.696.7468151309.0 yarn add @magic-ext/terra@13.5.1-canary.696.7468151309.0 yarn add @magic-ext/tezos@16.5.1-canary.696.7468151309.0 yarn add @magic-ext/webauthn@15.5.1-canary.696.7468151309.0 yarn add @magic-ext/zilliqa@16.5.1-canary.696.7468151309.0 yarn add @magic-sdk/commons@17.5.1-canary.696.7468151309.0 yarn add @magic-sdk/pnp@15.6.1-canary.696.7468151309.0 yarn add @magic-sdk/provider@21.5.1-canary.696.7468151309.0 yarn add @magic-sdk/react-native-bare@22.5.1-canary.696.7468151309.0 yarn add @magic-sdk/react-native-expo@22.5.1-canary.696.7468151309.0 yarn add magic-sdk@21.5.1-canary.696.7468151309.0 ```