[JENKINS-55521] Allow for random resource return.

When getting a resource, I'd like to way to get a random resource. The current behavior seems to return the first on the stack. This ends with one resource getting used more then the others but I'd like to be able to randomize the resource returned.

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Originally reported by mdelaney, imported from: Allow for random resource return.

• status: Open
  
• priority: Minor
  
• component(s): lockable-resources-plugin
  
• resolution: Unresolved
  
• votes: 5
  
• watchers: 5
  
• imported: 20251217-081411
  

When getting a resource, I'd like to way to get a random resource. The current behavior seems to return the first on the stack. This ends with one resource getting used more then the others but I'd like to be able to randomize the resource returned.

environment

```
Jenkins: 1.150.1

Lockable resource plugin: 2.3
```

No files or tests are named. Start by locating the lockable-resources-plugin resource acquisition path and its existing selection behavior, then inspect related tests. Done means a resource can be selected randomly without breaking current locking behavior, with tests documenting the new option or behavior.

Written by the indexing model from the issue text.