Bash completion error

**What steps did you take:**

```bash
source <(vendir completion bash)
```

**What happened:**

```bash
source <(vendir completion bash)
bash: Succeeded: command not found
echo $?
127
```

**What did you expect:**

```bash
source <(vendir completion bash)
echo $?
0
```

**Anything else you would like to add:**

A minor issue for the team is when loading bash completion, the word "Succeeded" is printed to stdout as per [here](https://github.com/carvel-dev/vendir/blob/bc7a968800ebec21b2dd0d3782e359fdbed0e0ca/cmd/vendir/vendir.go#L37).

When sourced as shown above, this causes bash to try and run `Succeeded` as a command resulting in

```bash
bash: Succeeded: command not found
```

A workaround is as follows but would be nice to be the same as other carvel tools.

```bash
source <(vendir completion bash | grep -v "Succeeded")
```

**Environment:**

- Debian Linux

```bash
PRETTY_NAME="Debian GNU/Linux 12 (bookworm)"
NAME="Debian GNU/Linux"
VERSION_ID="12"
VERSION="12 (bookworm)"
VERSION_CODENAME=bookworm
ID=debian
HOME_URL="https://www.debian.org/"
SUPPORT_URL="https://www.debian.org/support"
BUG_REPORT_URL="https://bugs.debian.org/"
```

- vendir version `v0.34.3`

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Start at cmd/vendir/vendir.go line 37 and inspect the output produced by `vendir completion bash`. Run `source <(vendir completion bash)` before and after the change, confirming that no `Succeeded` text is emitted and the command exits with status 0.

Written by the indexing model from the issue text.