Here's an image for using the latest android-tools. You can also install it with apk, but the version is old.
This image is using frolvlad/alpine-glibc because I need glibc to use android-tools.
/ # apk --update-cache --repository http:https://dl-3.alpinelinux.org/alpine/edge/testing/ --no-cache add android-tools
…
/ # adb --version
Android Debug Bridge version 1.0.41
Version 29.0.6-android-tools
Installed as /usr/bin/adb
/ # adb --version
Android Debug Bridge version 1.0.41
Version 30.0.4-6686687
Installed as /usr/local/android/platform-tools/adb