Fix mysqldump ignoring errors (#403)

* Add schema and tables for the tests

* Add tests for full dump with and without compression

* Add test for distinct dump with and without compression

* Fix sh not seeing errors for command before the pipe

sh is missing the pipefail flag. We must use bash for this.

* Add cleanup to prevent the following tests from failing

* Fix fqcn in module_defaults

* Add changelog fragment

* Add check to the error message to ensure we captured the right one

* Add option to activate the fix on systems with bash

* Fix errors when data schema is already absent

* Update changelogs/fragments/fix-256-mysql_dump-errors.yml

Co-authored-by: Andrew Klychkov <aaklychkov@mail.ru>

* Add markup for commands in the documentation string

Co-authored-by: Andrew Klychkov <aaklychkov@mail.ru>

* Add markup and next release version in the documentation string

Co-authored-by: Andrew Klychkov <aaklychkov@mail.ru>

* Fix missing dependency for MySQL 8

* Add pipefail to tests of uncompressed dumps to enure it still works

* Fix "bash command not found" if pipefail is used for uncompressed dump

* Fix sanity pep8

* Document example of dump with pipefail

* Add dedpulication to command construct

Co-authored-by: Andrew Klychkov <aaklychkov@mail.ru>

Co-authored-by: Andrew Klychkov <aaklychkov@mail.ru>

tests/integration/targets/setup_mysql/vars/main.yml

@@ -19,6 +19,7 @@ install_prereqs:
 
 install_python_prereqs:
   - python3-dev
+  - python3-cryptography
   - default-libmysqlclient-dev
   - build-essential