search: Standardize created file permissions
- Default umask to 0027. This makes everything group readable, and world unreadable.
- Separately, as part of the task, all directory ownership was changed to analytics-search:analytics-privatedata-users. Combined this results in the data generally being readable but only writable by the analytics-search user.
- We had
merged_default_args
anddefault_args
depending on construction in various dags. Normalize todefault_args
everywhere as the distinction isn't meaningful. - We had various ways of combining conf dictionaries to pass into the spark operator. Standardize the method so it's the same everywhere.
Bug: T374637