Update arm64 and arm32 builds from Mariner 2 to Azure Linux 3

[Copilot]

Migrate arm64 and arm32 build pools to Azure Linux 3 images with separate public/internal image references.

Changes

• common.yml: Replace single linuxArm64PoolImage with:

  • linuxArm64PublicPoolImage: azure-linux-3-arm64-public
  • linuxArm64InternalPoolImage: azure-linux-3-arm64

• common.yml: Replace single linuxArm32PoolImage with:

  • linuxArm32PublicPoolImage: azure-linux-3-arm64-public
  • linuxArm32InternalPoolImage: azure-linux-3-arm64

• build-and-test.yml: Update linuxArm64Pool and linuxArm32Pool to select image based on project type, using demands syntax for public pools and image for internal pools

Original prompt

On common.yml:21-33, See eng/docker-tools/templates/variables/dotnet/common.yml#L21-L33. For arm64 builds, we need to update from mariner 2 to azure linux 3. There are new images in docker-linux-arm-internal and docker-linux-arm-public. The images are azure-linux-3-arm64 (for the internal pool) and azure-linux-3-arm64-public.

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