`amplify env pull --envName <env-name>` does not work as expected, pulls current env

### Before opening, please confirm:

- [X] I have installed the latest version of the Amplify CLI (see above), and confirmed that the issue still persists.
- [X] I have [searched for duplicate or closed issues](https://github.com/aws-amplify/amplify-cli/issues?q=is%3Aissue+).
- [X] I have read the guide for [submitting bug reports](https://github.com/aws-amplify/amplify-cli/blob/dev/CONTRIBUTING.md#bug-reports).
- [X] I have done my best to include a minimal, self-contained set of instructions for consistently reproducing the issue.
- [X] I have removed any sensitive information from my code snippets and submission.

### How did you install the Amplify CLI?

pnpm

### If applicable, what version of Node.js are you using?

18

### Amplify CLI Version

10.5.1

### What operating system are you using?

mac

### Did you make any manual changes to the cloud resources managed by Amplify? Please describe the changes made.

n/a

### Amplify Categories

Not applicable

### Amplify Commands

Not applicable

### Describe the bug

see title. When running `amplify env pull --envName `, the CLI will only pull the current environment. This command is recommended to users when they opt to NOT modify their project's backend on `amplify pull` as shown here https://github.com/aws-amplify/amplify-cli/issues/11066#issuecomment-1261047852

### Expected behavior

the command pulls the specified env

### Reproduction steps

1. `amplify init -y`
2. `amplify env pull --envName doesnotexist`
3. observe CLI fetched current `dev` environment

### GraphQL schema(s)

```graphql
# Put schemas below this line

```

### Project Identifier

_No response_

### Log output

```
# Put your logs below this line

```

### Additional information

_No response_

Start by tracing the Amplify CLI's `env pull` command and how it handles the `--envName` argument, then reproduce the behavior with a nonexistent or alternate environment as described. Done means the command targets the requested environment and does not silently pull the current one; add or update coverage for the argument handling if the existing command tests expose it.

Written by the indexing model from the issue text.