[Bug][Test-only]: gcs bucket leak in yaml tests

[Abacn]

Related Template(s)

Yaml Templates

Template Version

N/A

What happened?

There are modest resource leaks happened to Yaml templates. There are leftover gcs buckets named after e.g.

icebergtomysqlyamlit-20260409-9d84e96f-4489-4827-8c30-962a4efd1

The buckets are intiialized here:

DataflowTemplates/yaml/src/test/java/com/google/cloud/teleport/templates/yaml/MySQLToIcebergYamlIT.java

Line 74 in ac1967e

GcsResourceManager.builder(getClass().getSimpleName(), credentials).build();

and in other tests.

They all have a "iceberg_namespace" top level folder.

We should use a pre-existing bucket if possible, and set "iceberg_namespace" uuid suffixes to avoid conflict. This bucket can be setup with a lifecycle policy to delete old orphan files

Relevant log output

[Abacn]

cc: @derrickaw