Bump version to 6.13.0


Change-Id: I5a3a3210aca0451b8265ca090598f254bb1c3ff1
Reviewed-by: Qt Submodule Update Bot <qt_submodule_update_bot@qt-project.org>
commita180e5a22562e12bad2c035ae046a670d08db430
parent186eb972a408b72421415206b6c530eba53602b6
authorJani Heikkinen <jani.heikkinen@qt.io>
committerJani Heikkinen <jani.heikkinen@qt.io>
commit timeSat, 13 Jun 2026 00:34:56 +0000