bug: Add missing " in date-cpp package reference

[hno-addiva]

Description

Almost cosmetic bugfix adding a missing " in date-cpp package reference, which caused a build time warning

• [x] Bugfix
  • [ ] Regression tests
  • [ ] ChangeLog updates (for next release)
• [ ] Feature
  • [ ] YANG model change => revision updated?
  • [ ] Regression tests added?
  • [ ] ChangeLog updates (for next release)
  • [ ] Documentation added?
• [ ] Code style update (formatting, renaming)
• [ ] Refactoring (please detail in commit messages)
• [ ] Build related changes
• [ ] Documentation content changes
• [ ] Other (please describe):