Merge pull request #373153 (update aqbanking)

This updates AqBanking and Gwenhywfar to their most recent versions.

Since the upstream project didn't provide changelogs, here are the Git
subject lines for AqBanking:

  * prepared release 6.6.0
  * added aqofxconnect-tool to .gitignore
  * added missing .gitignore
  * csv: added profile for comdirect depot status reports.
  * aqhbci: fixed a bug (was not clearing "MODIFIED" flag in _saveUser)
  * Improved im/exporter script for CAMT 053.001.02 (thanks to Jan Vlug)
  * configure pain.001.001.09 as a sepa profile
  * add pain.001.001.09 profile to xml imexporter
  * configure pain.001.001.03 as a sepa profile
  * fix typo in description field
  * aqhbci: only mark pin "bad" if the server reports it as such.
  * aqhbci: added methodId "Q1S" to map. Increased verbosity.
  * increased verbosity, retry gmp_snprintf() on error
  * New version submitted by Jan Vlug. Thanks!

... and for Gwenhywfar:

  * Released 5.12.0
  * Prepared release 5.12.0
  * msgio: add argument REASON to GWEN_MsgRequest_Abort()
  * msgio: add class GWEN_REQUEST.
  * msgio/endpoint: added reference counter.
  * timestamp: added GWEN_Timestamp_AddSeconds().
  * msgio: improved error handling.
  * test: adjusted to latest changes.
  * parser: fixed a typo.
  * msgio: added fields ID and REFID to ipc messages. Use new
    convenience fns of GWEN_MSG.
  * msgio: added missing change.
  * msgio: improved GWEN_MSG, added convenience functions.
  * msgio: introduce GWEN_MsgEndpoint_GetNextMessageId()
  * Use pkgconf for gpg-error build flags
  * Fixed call to readlink().
  * gsa: fixed handling of symbolic links.
  * incremented version.
  * gwenbuild: use lstat if possible (otherwise symbolic links will be
    resolved).
  * gwenbuild: also install symbolic links for libs.

I didn't do a thorough test of whether AqBanking fully works since I
don't have that setup while on the road. But given that rudimentary
tests of aqbanking-cli and aqhbci-tool4 work, I think it's very unlikely
that this would introduce a lot of bugs on our end.