Fix test data issue when large project description is missing

Will be released as 1.0.5

MR adds safeguard for the vertical data generation if large project description is missing. This could happen if in the first run large project import failed.

Additionally, manual job for the Generator check was introduced.

Failure example

Logs:

| Vertical data: importing large projects for GPT...
Group test/large_projects already exists
Checking if project test1 already exists in test/large_projects/test1...
Project test/large_projects/test1 already exists

GPT data generation failed:
undefined method `match' for nil:NilClass
 Traceback:["/GitLab/performance/lib/gpt_test_data.rb:316:in `block in create_vertical_test_data'", "/GitLab/performance/lib/gpt_test_data.rb:297:in `each'", "/GitLab/performance/lib/gpt_test_data.rb:297:in `with_index'", "/GitLab/performance/lib/gpt_test_data.rb:297:in `create_vertical_test_data'", "bin/generate-gpt-data:122:in `<main>'"]