CI: Use QT_QPA_PLATFORM=offscreen

Initialize seed with std::time if not user-supplied

Closes #2026

See merge request orfeotoolbox/otb!705

Fix warnings

Closes #2015

See merge request orfeotoolbox/otb!696

WRG: silence warning 4275 : non-DLL-interface std::runtime_error used as base for DLL-interface Error

Pantex texture extraction application

Closes #2022

See merge request orfeotoolbox/otb!704

WRG: move gl::error implementation to the header so it is not exported in a dll in windows as std::runtime_error is not a dll interface (C4275)

ENH: new PantexTextureExtraction application built around the ScalarImageToPanTexTextureFilter filter

Release 7.1

See merge request orfeotoolbox/otb!703

BUG: updated multi baselines for ioTvMultiDatasetReading 1 and 2, 'Not specified based on custom spheroid' is not formatted is the same way between different gdal versions

DOC: correct filthy typo

Closes #2034

See merge request orfeotoolbox/otb!702