MDL-45699 behat: can now use alt cache config
MDL-45699 cache: acceptance test improvements

We now use the unit test cache config class when running
acceptance tests so that the same defines are applicable there.
MDL-45699 cache: renamed cache_config_phpunittest

Renamed cache_config_phpunittest to cache_config_testing
MDL-48568 cache: stores now determine testing

Cache stores are now responsible for deciding if they are suitable
for use as the primary cache store during unit and acceptance tests

Changes are as follows:
* New method: cache_store::ready_to_be_used_for_testing
* Core cache store have been updated to override this method as
  required.
* MongoDB usesafe default changed to true to match actual default
  behaviour.
MDL-48224 cron: Buffer SMTP connections around tasks
MDL-48088 calendar: normalize DTEND, add romance standard time

Thanks to Cedric Mortiers (cmortiers@stjohns.be) for providing the patch.
MDL-46124 libraries: Final deprecation of text libs and plugin libs

- textlib_get_instance
- textlib
- collatorlib
- plugin_manager
- plugininfo_base
MDL-48445 report_loguser: Include logstore parameter for pagination
MDL-48580 report_log: fix site errors dropdown

Thanks Renaat Debleu for pointing this bug and share a solution.
MDL-42166 repositories: Finalise deprecation of repository sync methods
MDL-48593 messageinbound: Correct header retrieval from IMAP server

Header retrieval should only be performed on the base message, and not each
part of the message as is currently performed.

This came to light because Google changed their IMAP server such that, if
you inform the data query that you wish to retrieve the headerText for a
part which does not contain a MIME header, then no message is retrieved in
the search causing a general failure of the IMAP fetch.

In normal circumstances, headers should only be a part of the base message
part.
MDL-44260 core_file: final deprecation of upload_manager class and clam functions
MDL-44260 core_deprecated: final deprecation of clam related methods
MDL-48534 mod_assign: display correct workflow state and marker
MDL-43004 blog: Deprecation of parameter $action in add_association/s()
MDL-43730 mod_book: Make chapter action links accessible
MDL-43730 mod_book: Automate MDLQA-2426

Behat feature to make sure show/hide feature for book chapter works as expected
MDL-48423 messages: improved accessibility of contacts list
MDL-48591 calendar: Mini Cal Display DST Events
MDL-48638 database SQL: Fix typo in exception constructor