Pin the container image versions used for job runners

[mhucka]

The containers used on the linux-x86-n2-32 runners were referenced using latest. For better reproducibility of results, this changes the version to a specific image tag.

Details about the Docker image we are currently:

• The container image is pulled from us-docker.pkg.dev/ml-oss-artifacts-published/ml-public-container/ml-build
• We are currently using the image with the tag infrastructure-public-image-82c7ac59ba4b
  • This is based on Ubuntu 22.04
  • The container image is built by a Dockerfile and associated scripts in the TensorFlow GitHub repo found at ci/official/containers/ml_build
  • The specific copy of that Dockerfile and the other files is what existed at git commit 2658e16b3cba8dfa7e95e762a21028b6eff1616c

[MichaelBroughton]

LGTM!