Release: Updates for the 4.2 branch

* Version bumps and pointing gitmodules to the branch.
* Splash screen by Blender Studio (studio.blender.org)

.gitmodules

@@ -2,33 +2,33 @@
 	update = none
 	path = lib/linux_x64
 	url = https://projects.blender.org/blender/lib-linux_x64.git
-	branch = main
+	branch = blender-v4.2-release
 [submodule "lib/macos_arm64"]
 	update = none
 	path = lib/macos_arm64
 	url = https://projects.blender.org/blender/lib-macos_arm64.git
-	branch = main
+	branch = blender-v4.2-release
 [submodule "lib/macos_x64"]
 	update = none
 	path = lib/macos_x64
 	url = https://projects.blender.org/blender/lib-macos_x64.git
-	branch = main
+	branch = blender-v4.2-release
 [submodule "lib/windows_x64"]
 	update = none
 	path = lib/windows_x64
 	url = https://projects.blender.org/blender/lib-windows_x64.git
-	branch = main
+	branch = blender-v4.2-release
 [submodule "lib/windows_arm64"]
     update = none
 	path = lib/windows_arm64
 	url = https://projects.blender.org/blender/lib-windows_arm64.git
-	branch = main
+	branch = blender-v4.2-release
 [submodule "release/datafiles/assets"]
 	path = release/datafiles/assets
 	url = https://projects.blender.org/blender/blender-assets.git
-	branch = main
+	branch = blender-v4.2-release
 [submodule "tests/data"]
 	update = none
 	path = tests/data
 	url = https://projects.blender.org/blender/blender-test-data.git
-	branch = main
+	branch = blender-v4.2-release