Merge branch 'master' into jgrpp

# Conflicts:
#	src/airport_gui.cpp
#	src/build_vehicle_gui.cpp
#	src/direction_type.h
#	src/gfx_type.h
#	src/group_gui.cpp
#	src/misc_gui.cpp
#	src/rail_gui.cpp
#	src/road_gui.cpp
#	src/signs_gui.cpp
#	src/slope_func.h
#	src/smallmap_gui.cpp
#	src/terraform_gui.cpp
#	src/toolbar_gui.cpp
#	src/town_gui.cpp
#	src/town_type.h
#	src/vehicle_type.h
#	src/widget_type.h

.github/workflows/ci-build.yml

@@ -87,12 +87,12 @@ jobs:
       matrix:
         include:
         - name: Clang - Debug
-          compiler: clang
-          cxxcompiler: clang++
+          compiler: clang-15
+          cxxcompiler: clang++-15
           libraries: libsdl2-dev
         - name: Clang - Release
-          compiler: clang
-          cxxcompiler: clang++
+          compiler: clang-15
+          cxxcompiler: clang++-15
           libraries: libsdl2-dev
           extra-cmake-parameters: -DCMAKE_BUILD_TYPE=RelWithDebInfo -DOPTION_USE_ASSERTS=OFF
         - name: GCC - SDL2