WIP: fix gradle 7 error

[Andarius]

This PR is my attempt to fix #41.
For now it fails with

Execution failed for task ':externalNativeBuildDebug'.
> Build command failed.
  Error while executing process /home/Android/Sdk/cmake/3.10.2.4988404/bin/ninja with arguments {-C /home/Projects/react-native-skia/package/android/.cxx/cmake/debug/armeabi-v7a reactskia}
  ninja: Entering directory `/home/Projects/react-native-skia/package/android/.cxx/cmake/debug/armeabi-v7a'
  [1/6] Building CXX object CMakeFiles/reactskia.dir/cpp/jni/JniPlatformContext.cpp.o
  [2/6] Building CXX object CMakeFiles/reactskia.dir/cpp/jni/JniLoad.cpp.o
  [3/6] Building CXX object CMakeFiles/reactskia.dir/cpp/rnskia/RNSkManager.cpp.o
  FAILED: CMakeFiles/reactskia.dir/cpp/rnskia/RNSkManager.cpp.o 
  /home/Android/Sdk/ndk/21.4.7075529/toolchains/llvm/prebuilt/linux-x86_64/bin/clang++ --target=armv7-none-linux-androideabi16 --gcc-toolchain=/home/Android/Sdk/ndk/21.4.7075529/toolchains/llvm/prebuilt/linux-x86_64 --sysroot=/home/Android/Sdk/ndk/21.4.7075529/toolchains/llvm/prebuilt/linux-x86_64/sysroot  -Dreactskia_EXPORTS -I../../../../../node_modules/react-native/ReactCommon/callinvoker -I../../../../../node_modules/react-native/ReactCommon/jsi -I../../../../../node_modules/react-native/ReactCommon/react/nativemodule/core -I../../../../../node_modules/react-native/ReactAndroid/src/main/java/com/facebook/react/turbomodule/core/jni -I../../../../../../../react-native/ReactCommon/callinvoker -I../../../../../../../react-native/ReactCommon/jsi -I../../../../../../../react-native/ReactCommon/react/nativemodule/core -I../../../../../../../react-native/ReactAndroid/src/main/java/com/facebook/react/turbomodule/core/jni -I../../../../cpp/skia/include/config -I../../../../cpp/skia/include/core -I../../../../cpp/skia/include/effects -I../../../../cpp/skia/include/utils -I../../../../cpp/skia/include/pathops -I../../../../cpp/skia/modules -I../../../../cpp/skia/include -I../../../../cpp/skia -I../../../../cpp/api -I../../../../cpp/jsi -I../../../../cpp/jni/include -I../../../../cpp/rnskia -I../../../../cpp/utils -I../../../../build/fbjni-0.2.2-headers.jar -g -DANDROID -fdata-sections -ffunction-sections -funwind-tables -fstack-protector-strong -no-canonical-prefixes -D_FORTIFY_SOURCE=2 -march=armv7-a -mthumb -Wformat -Werror=format-security  -fexceptions -frtti -std=c++1y -DONANDROID -DSK_GL -DSK_BUILD_FOR_ANDROID -DFOLLY_NO_CONFIG=1 -DFOLLY_HAVE_CLOCK_GETTIME=1 -DFOLLY_HAVE_MEMRCHR=1 -DFOLLY_USE_LIBCPP=1 -DFOLLY_MOBILE=1 -DON_ANDROID -DONANDROID -O0 -fno-limit-debug-info  -fPIC   -std=gnu++1z -MD -MT CMakeFiles/reactskia.dir/cpp/rnskia/RNSkManager.cpp.o -MF CMakeFiles/reactskia.dir/cpp/rnskia/RNSkManager.cpp.o.d -o CMakeFiles/reactskia.dir/cpp/rnskia/RNSkManager.cpp.o -c ../../../../cpp/rnskia/RNSkManager.cpp
  In file included from ../../../../cpp/rnskia/RNSkManager.cpp:3:
  In file included from ../../../../cpp/api/JsiSkApi.h:7:
  ../../../../cpp/api/JsiSkRuntimeEffect.h:75:55: error: no member named 'size' in 'SkRuntimeEffect::ConstIterable<SkRuntimeEffect::Uniform>'
        return static_cast<int>(getObject()->uniforms().size());
                                ~~~~~~~~~~~~~~~~~~~~~~~ ^
  1 error generated.
  [4/6] Building CXX object CMakeFiles/reactskia.dir/cpp/jni/JniSkiaDrawView.cpp.o
  [5/6] Building CXX object CMakeFiles/reactskia.dir/cpp/jni/JniSkiaManager.cpp.o
  ninja: build stopped: subcommand failed.