Log the right amount of lint problems (#2024)

## Changes
Log the right amount of lint problems, now it is less than the actual
number. Incorrect message is introduced in #1956, fixing here.

Author: JCZuurmond

src/databricks/labs/ucx/source_code/jobs.py

@@ -298,8 +298,8 @@ def refresh_report(self, sql_backend: SqlBackend, inventory_database: str):
             tasks.append(functools.partial(self.lint_job, job.job_id))
         logger.info(f"Running {tasks} linting tasks in parallel...")
         job_problems, errors = Threads.gather('linting workflows', tasks)
-        logger.info(f"Saving {len(job_problems)} linting problems...")
         job_problems_flattened = list(itertools.chain(*job_problems))
+        logger.info(f"Saving {len(job_problems_flattened)} linting problems...")
         sql_backend.save_table(
             f'{inventory_database}.workflow_problems',
             job_problems_flattened,