Create CI partitions for partition_id 102

Ref: !148376 (merged)

What does this MR do and why?

Creates the following partitions:

• gitlab_partitions_dynamic.ci_build_names_102
• gitlab_partitions_dynamic.ci_builds_102
• gitlab_partitions_dynamic.ci_builds_metadata_102
• gitlab_partitions_dynamic.ci_job_annotations_102
• gitlab_partitions_dynamic.ci_job_artifacts_102
• gitlab_partitions_dynamic.ci_pipeline_variables_102
• gitlab_partitions_dynamic.ci_runner_machine_builds_102
• gitlab_partitions_dynamic.ci_stages_102

And adds a new feature flag to switch writes to these partitions.

Related to gitlab-com/gl-infra/scalability#3180 (comment 1836728421)

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