Add in process executable entity #2655

[thompson-tomo]

Progresses #2655

Changes

This introduces a new process executable entity which describes the executable being run by the process.

This entity is designed to be consistent across all instances regardless of machine or where files are placed.

Note: if the PR is touching an area that is not listed in the existing areas, or the area does not have sufficient domain experts coverage, the PR might be tagged as experts needed and move slowly until experts are identified.

Merge requirement checklist

• [x] CONTRIBUTING.md guidelines followed.
• [x] Change log entry added, according to the guidelines in When to add a changelog entry.
  • If your PR does not need a change log, start the PR title with [chore]
• [ ] Links to the prototypes or existing instrumentations (when adding or changing conventions)