Added support for multiple labels in keywords

[jesper-friis]

Description

Added support for multiple labels in keywords.

Type of change

• Bug fix and code cleanup
• New feature
• Documentation update
• Testing

Checklist for the reviewer

This checklist should be used as a help for the reviewer.

• Is the change limited to one issue?
• Does this PR close the issue?
• Is the code easy to read and understand?
• Do all new feature have an accompanying new test?
• Has the documentation been updated as necessary?
• Is the code properly tested?

[codecov]

Codecov Report

❌ Patch coverage is 52.94118% with 8 lines in your changes missing coverage. Please review.
✅ Project coverage is 84.60%. Comparing base (35d1047) to head (cb1ec14).
⚠️ Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
tripper/datadoc/dataset.py	27.27%	8 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #508      +/-   ##
==========================================
- Coverage   84.72%   84.60%   -0.13%     
==========================================
  Files          30       30              
  Lines        4858     4872      +14     
==========================================
+ Hits         4116     4122       +6     
- Misses        742      750       +8     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[francescalb]

OK, as a first fix