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>

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

@@ -0,0 +1,7 @@
+---
+
+bugfixes:
+  - mysql_dump - Fixes issue 256. Using compression masks errors messages from
+    mysql_dump. By default the fix is inactiv to ensure retro-compatibility
+    with system without bash. To activate the fix, use the module option
+    ``pipefail=true`` (https://github.com/ansible-collections/community.mysql/issues/256).