Change XML field name in EXIT file from forward model

[berland]

job -> step.

Issue
Resolves naming inconsistency jobs vs step for the XML EXIT file left in the runpath.

This is potentially a breaking change.

Approach
Short description of the approach

(Screenshot of new behavior in GUI if applicable)

• PR title captures the intent of the changes, and is fitting for release notes.
• Added appropriate release note label
• Commit history is consistent and clean, in line with the contribution guidelines.
• Make sure unit tests pass locally after every commit (git rebase -i main --exec 'just rapid-tests')

When applicable

• When there are user facing changes: Updated documentation
• New behavior or changes to existing untested code: Ensured that unit tests are added (See Ground Rules).
• Large PR: Prepare changes in small commits for more convenient review
• Bug fix: Add regression test for the bug
• Bug fix: Create Backport PR to latest release

[codspeed-hq]

CodSpeed Performance Report

Merging #10020 will improve performances by 11.8%

_{Comparing berland:job_step_in_xml (3205f61) with main (718834e)}

Summary

⚡ 1 improvements
✅ 24 untouched benchmarks

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
⚡	test_direct_dark_performance_with_storage[gen_x: 20, sum_x: 20 reals: 10-gen_data_with_obs-get_record_observations]	2.7 ms	2.4 ms	+11.8%

[andreas-el]

💯

[berland]

Pinging @sondreso for second opinion on user impact. Breaking?

[sondreso]

I think this counts as a breaking change yes, and we should mark it as such. But the actual impact on users should be low, so I'm in favor of merging this.

[berland]

This is blocked from merging until there is another breaking change that comes along. This is to avoid version number inflation.