Added 'ms' duration to gantt diagram

[vallsv]

📑 Summary

Hi. This PR features task duration in milliseconds.

Resolves #3028

    gantt
      title A Gantt Diagram
      dateFormat x
      axisFormat %L
      section Section
      A task           :a1, 0, 30ms
      Another task     :after a1, 20ms
      section Another
      Another another task      :b1, 20, 12ms
      Another another another task     :after b1, 24ms

📏 Design Decisions

No crazy things

• Fix the regex to match multi character including ms
  • Previously the string was not matched until the end -> 10ms was matched as 10 minutes
  • The side effect is now a duration like 10mhj will probably not be matched anymore -> which is IMO better
• Use ms to properly convert the duration in millisecond

📋 Tasks

Make sure you

• 📖 have read the contribution guidelines
• 💻 have added unit/e2e tests (if appropriate)
• 🔖 targeted develop branch

[Yash-Singh1]

LGTM!