bug: Fix deploymentnames in pipeline-scripts to max 64 char

[picccard]

Overview/Summary

Bug in the pipeline-scripts causes the the date to be limited to 64 chars, instead of limiting the entire deploymentname to be max 64 chars. This PR fixes this.

As part of this Pull Request I have

• [x] Read the Contribution Guide and ensured this PR is compliant with the guide
• [ ] Ensured the resource API versions in .bicep file/s I am adding/editing are using the latest API version possible
• [x] Checked for duplicate Pull Requests
• [x] Associated it with relevant GitHub Issues
• [ ] (ALZ Bicep Core Team Only) Associated it with relevant ADO Items
• [x] Ensured my code/branch is up-to-date with the latest changes in the main branch
• [ ] Performed testing and provided evidence.
• [ ] Updated one or more of the following tests (if required)
  • Unit
  • Linting
  • E2E (End-To-End)
  • ValidateAzCloud (Base validation in Azure Cloud)
  • ValidateMcCloud (Base validation in Azure China Cloud)
• [ ] Updated relevant and associated documentation (e.g. Contribution Guide, Module READMEs, Wiki Docs etc.)
• [ ] If relevant, created or updated Code Tours here

[oZakari]

Thanks @picccard! Before I merge, I'll update the readme's with this change as well.