Add CLI tests for workbook, execution and task

Were added tests which check CLI commands for work with workbooks,
executions and tasks.
Tests check:
- structure of return table,
- object creation, deletion
- uploading definition

Targets blueprint: mistral-cli-integrational-tests
Change-Id: Iaca6a547678bd0594e5deb8b159578fea356ded1
Merge "Add CLI tests for workbook, execution and task"