Modular-sdk

- Add util to trace Jobs execution result
- Add util to trace Runtime/ScheduleRuntime segment execution result

- fix limit and last evaluated key in PynamoDBToPymongoAdapter and refactor a bit
- add `limit` and `last_evaluated_key` params to `i_get_tenant_by_customer`
and `scan_tenants` methods in tenant service;
- refactor `BaseModel` and add an ability for potential users of SDK to
use the PynamoToMongoAdapter and BaseModel from SDK, providing their
MongoDB credentials and url

- fixed expiration in cross-account access;
- added `classproperty` decorator to helpers;
- added new possible env `modular_AWS_REGION`. It has priority over `AWS_REGION`
and can be useful if MODULAR Tables are situated in a different region from
the tool that uses MODULAR SDK;
- added functions `utc_iso` and `utc_datetime` instead of `get_iso_timestamp`;

- added `customer_id` - `type` index to `Application` model;
- added `key` - `tenant_name` index to `TenantSettings` model;
- added `CUSTODIAN:CUSTOMER` to the list of available Parent types;
- Made `modular.models.pynamodb_extension.pynamodb_to_pymongo_adapter.Result`
iterator instead of list;
- updated `pynamodb` version to `5.2.3`;
- fixed bugs with tenant regions;
- added some method to services to query entities in different ways;

Added
- Initial version of Modular SDK.