Update base image to Debian Bookworm

[bobidle]

Adjustments to use Debian Bookworm as base image. Only the build via docker was tested.

Successful test builds

Docker Image :emulator ✅

docker build -f emulators/Dockerfile -t google-cloud-cli:emulators --build-arg CLOUD_SDK_VERSION=458.0.0 emulators/

Docker Image :slim ✅

docker build -f debian_slim/Dockerfile -t google-cloud-cli:slim --build-arg CLOUD_SDK_VERSION=458.0.0 debian_slim/

Docker Image :debian_component_based ✅

docker build -f debian_component_based/Dockerfile -t google-cloud-cli:debian_component_based --build-arg CLOUD_SDK_VERSION=458.0.0 debian_component_based/

Failed test builds

Docker Image :latest ❌

docker build -f Dockerfile -t google-cloud-cli:latest --build-arg CLOUD_SDK_VERSION=458.0.0 .

Error message

Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 google-cloud-cli-app-engine-python : Depends: python2.7 but it is not installable
E: Unable to correct problems, you have held broken packages.

Fix #345

[bobidle]

I updated the lines in the Dockerfiles according to the latest docs entries

For newer distributions (Debian 9+ or Ubuntu 18.04+) run the following command:

curl https://packages.cloud.google.com/apt/doc/apt-key.gpg | sudo gpg --dearmor -o /usr/share/keyrings/cloud.google.gpg

echo "deb [signed-by=/usr/share/keyrings/cloud.google.gpg] https://packages.cloud.google.com/apt cloud-sdk main" | sudo tee -a /etc/apt/sources.list.d/google-cloud-sdk.list

https://cloud.google.com/sdk/docs/install#deb

@cloudsdkdocker via commit e96ec52 the gpg key usage in an apt source list was reverted.

Are the changes from the docs still problematic and might break the build? I can't reproduce any failures locally.

[bobidle]

In Google Cloud CLI v486.0.0 (2024-03-12) Python 2 is no longer supported by App Engine. But the Debian packages still depends on it.