Regenerate datacatalog client

[yoshi-automation]

This PR was generated using Autosynth. 🌈

Here's the log from Synthtool:

synthtool > Executing /tmpfs/src/git/autosynth/working_repo/google-cloud-clients/google-cloud-datacatalog/synth.py.
synthtool > Ensuring dependencies.
synthtool > Pulling artman image.
latest: Pulling from googleapis/artman
Digest: sha256:6068f67900a3f0bdece596b97bda8fc70406ca0e137a941f4c81d3217c994a80
Status: Image is up to date for googleapis/artman:latest
synthtool > Cloning googleapis.
synthtool > Running generator for google/cloud/datacatalog/artman_datacatalog_v1beta1.yaml.
synthtool > Generated code into /home/kbuilder/.cache/synthtool/googleapis/artman-genfiles/java.
synthtool > Running java formatter on 10 files
synthtool > Running java formatter on 1 files
synthtool > Running java formatter on 96 files
synthtool > Cleaned up 1 temporary directories.
synthtool > Wrote metadata to synth.metadata.

[shollyman]

This is a large set of changes and new methods, so I'm relying on the fact that more incremental reviews were done upstream of this generation.

Many of the deltas are triggered by an increase in method/field comments and annotations (yay). There appears to be new alpha-yet-public additions to the API surface. The previously identified issue around field flattening for IAM methods is addressed here.

The service itself is beta and changes are expected, so approving.