Draft: Add table for storing run steps for build execution config

What does this MR do and why?

We are adding the required table and schema changes to support #453957

This MR adds a table called p_ci_builds_execution_configs to store the run_steps (for now) as jsonb column.

The p_ci_builds table will have a FK to this table, each config can have many builds, but each build will belong to only one config. If retried, the same config will be referenced to the new build.

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Related to #453957