[TAL-696] Customize Dockerfile

[chingkt]

The image is pushed to this repository: https://hub.docker.com/repository/docker/heyjobs/ecs-deploy-multiple-images/general

This PR is related to https://github.com/heyjobs/jobseeker-portal/pull/4030

This PR adds some customizations to the Dockerfile:

1. specify platform to amd64, otherwise the default arch would be arm64, which is not supported by the current circleci host.
2. Due to this error, we use alpine 3.15 instead of the latest minor version. Starting from 3.16, there has been a dependency issue against glibc with versions lower than 2.35-r0: ERROR: glibc-2.35-r0: trying to overwrite etc/nsswitch.conf owned by alpine-baselayout-data-3.3.0-r2. sgerrand/alpine-pkg-glibc#185. Our circleci aws-cli orb still uses 2.34, so until they resolve this issue, we might want to stay with 3.15 if we don't want to spend too much time on it.
3. install bash, as aws-cli orb uses feature from bash