Update CI configurations (#2347)

* Update CircleCI docker image for Android

* Upgrade Gradle version to 7.5 and AGP to 7.4.2

* 'compileSdkVersion' -> 'compileSdk'

* Specify NDK version in gradle script

* Remove ndk.dir setting from Android CI config

* Update vcpkg version used for Windows CI

* Update github actions macos runners to macos-12

* Fix imgui formatting arguments

* Use embedded imgui instead of vcpkg for Windows