Cross-compiling from Ubuntu for aarch64

In the table of supported platforms it looks like the only way to target arm64 architecture for lambda is to compile on Amazon Linux 2.

Would it be possible to support cross-compiling from other OS's? Specifically Ubuntu 22.04?

My lambda function seems to build fine but its an error in the packaging stage:

```
cd .../build/lambda/src/aws && ../../vcpkg_installed/arm64-linux-release/share/aws-lambda-runtime/packager .../build/lambda/src/aws/test_lambda
not a dynamic executable
make[3]: *** [src/aws/CMakeFiles/aws-lambda-package-test_lambda.dir/build.make:73: src/aws/CMakeFiles/aws-lambda-package-test_lambda] Error 1
make[3]: Leaving directory '.../build/lambda'
make[2]: *** [CMakeFiles/Makefile2:3032: src/aws/CMakeFiles/aws-lambda-package-test_lambda.dir/all] Error 2
make[2]: Leaving directory '.../build/lambda'
make[1]: *** [CMakeFiles/Makefile2:3039: src/aws/CMakeFiles/aws-lambda-package-test_lambda.dir/rule] Error 2
make[1]: Leaving directory '..../build/lambda'
make: *** [Makefile:213: src/aws/CMakeFiles/aws-lambda-package-test_lambda.dir/rule] Error 2
```

Comience con la tabla «supported-platforms» y la invocación de aws-lambda-runtime/packager mostrada en el informe, y después reproduzca el objetivo de empaquetado de CMake en Ubuntu 22.04 para arm64. Se considera terminado cuando el objetivo test_lambda se empaqueta correctamente desde Ubuntu sin el error «not a dynamic executable» y la documentación de las plataformas compatibles refleja el resultado.

Escrito por el modelo de indexación a partir del texto del issue.