[Confidential Ledger] set up pipeline to run tests nightly (Azure#23130)

### Packages impacted by this PR
`confidentialledger`

### Issues associated with this PR


### Describe the problem that is addressed by this PR


### What are the possible designs available to address the problem? If there are more than one possible design, why was the one in this PR chosen?


### Are there test cases added in this PR? _(If not, why?)_
We are using the existing test cases.

### Provide a list of related PRs _(if any)_


### Command used to generate this PR:**_(Applicable only to SDK release request PRs)_

### Checklists
- [ ] Added impacted package name to the issue description
- [ ] Does this PR needs any fixes in the SDK Generator?** _(If so, create an Issue in the [Autorest/typescript](https://github.com/Azure/autorest.typescript) repository and link it here)_
- [ ] Added a changelog (if necessary)

Author: deer-prudence