[Release] Bump 1.59.x version to 1.59.0-pre1 (grpc#34490)

[Release] Bump version to 1.58.1 (on v1.58.x branch) (grpc#34336)

Change was created by the release automation script. See go/grpc-release

[Release] Bump version to 1.58.0 (on v1.58.x branch) (grpc#34261)

Change was created by the release automation script. See go/grpc-release

[Release] Bump version to 1.58.0-pre1 (on v1.58.x branch) (grpc#34145)

Change was created by the release automation script. See go/grpc-release

[Release] Bump version to 1.57.0 (on v1.57.x branch) (grpc#34008)

Change was created by the release automation script. See go/grpc-release

[v1.55.x][Interop] Backport Python image update (grpc#33866)

Update Phusion base image to address security issues. Original PR:
grpc#33847

[v1.54.x][Interop] Backport Python image update (grpc#33865)

Update Phusion base image to address security issues. Original PR:
grpc#33847

[v1.53.x][Interop] Backport Python image update (grpc#33864)

Update Phusion base image to address security issues. Original PR:
grpc#33847

[backport][test] Run PHP distribtests with make -j8 (grpc#33831) (grp…

…c#33834)

Related to grpc#33795.

The tests are still OOMing, and I found that this distribtest script is
still running `make -j ...` on a 16-core machine. Reducing it to `8` to
see if that helps. Example OOM:

https://fusion2.corp.google.com/invocations/c306e6b9-24e3-498d-8971-3e914feea29b/log

[release] Bump release version to 1.56.2 (grpc#33705)

Generated by release script