Add placeholder default values to the views' GadgetFields

- Reduce maximum data chunk size for new data
- Add a maximum data chunk size for the previous data to bound computing time

Moved to wendelin_telecom_test_data

Remove the problematic 'unsafe-eval' and 'unsafe-inline' directives

This version is now compatible with strict CSP setups

See merge request !2

See merge request !2

See merge request !2

See merge request !2

See merge request !2

Properly propagate destination_project to ingestion objects