generate-key with seed-phrase return wrong keypair

[hanakannzashi]

Describe the bug

When running near generate-key --seedPhrase="your seed phrase" (without providing --account_id <account>) for multiple times, every time a new random (rather than fixed) public key is returned even if the seed phrase keeps the same.

Example:

# 1st time
% near generate-key --seedPhrase="cow moon right send now cool dense quark pretty see light after"
Key pair with ed25519:9ETpmfmvHf4qcYz7UvCZgZhSZLin5PEAenRJ2ed2U1be public key for an account "7a50602085f66e7d2b963c9f8e7e09d5f5c2733dfdb0a4eb523caf9f4a74c061"

# 2nd time
% near generate-key --seedPhrase="cow moon right send now cool dense quark pretty see light after"
Key pair with ed25519:EXmwRyfmtWiHRp76YnDCdgsYyfqqbrdguQ8zciW4NfNh public key for an account "c90a2a98b6f1216ce44df6a2d7839d4790da9240774678cc88f2c6ca74fd429a"

Besides, it's quite weird that two json files are generated under the ~/.near-credentials/testnet folder: one is the right json file, while the other is wrong.

Screenshots

Update
I fixed this issue on PR#1036

[think-in-universe]

@hanakannzashi hey, feel free to add more description in the issue as it's hard to understand what the problem is.