Creds test definition parameter not optional

[timbrinded]

Issue Description

The Creds: config parameter for the test specs are non-optional, even when running zombienet with --provider native

Steps to reproduce the issue

Steps to reproduce the issue

1. Create a .zndsl spec with no Creds
2. Run the spec e.g. pnpm zombienet test --provider native configs/simple.zndsl

Describe the results you received

 Error: 	Error parsing file:  --> 4:1
  |
4 | relay-0: is up
  | ^---
  |
  = expected creds

error: "zombienet" exited with code 1

Describe the results you expected

The creds param to be skipped when zombienet test command is invoked with --provider native

Zombienet version

"@zombienet/cli": "^1.3.99"

Provider

Native

Provider version

polkadot 1.5.0

Upstream Latest Release

Yes

Additional environment details

Additional environment details

Additional information

Additional information like issue happens only occasionally or issue happens with a particular architecture or on a particular setting

Screenshots

No response

[pepoviola]

Hi @timbrinded, sorry about the delay. Yes, the creds are not optional even in native. I will update the parser to make them optional (at least in native/podman). Thanks!!