Add `PRE_BAZEL_INIT` variable to run a command before Bazel server starts.
Add `PRE_BAZEL_INIT` variable to run a command before Bazel server starts.

This is useful for initializing things that the Bazel server container
requires before starting in the first place.

PiperOrigin-RevId: 454265814

google/gvisor,google/gvisor,google/gvisor,google/gvisor,google/gvisor,google/gvisor,google/gvisor,google/gvisor