Fix performance regression in FormioData data structure

[sergei-maertens]

Closes #4744

Changes

Optimized key access in the FormioData data structure.

Performance results - the last column are the numbers for this PR. The gains are massive compared to master and they improve even on 2.7.x.

Form step	version: master (0ea7bfa)	version: 2.7.x	Perf patch
Inleiding	1540	736	448
Verklaring van waarheid	1520	751	464
Uw gegevens	1727	879	551
Uw situatie	1730	827	483
Gezinssamenstelling	1660	823	558
Uw inkomsten	1790	991	637
Uw inkomsten overzicht	1740	836	565
Inkomsten partner	1840	909	585
Inkomsten partner overzicht	1720	864	540
Bezit en schulden	1620	859	508
Bezit en schulden overzicht	1600	817	637
Post	1560	769	485
Overzicht	10350	4850	3330

Checklist

Check off the items that are completed or not relevant.

• Impact on features

  • [x] Checked copying a form
  • [x] Checked import/export of a form
  • [x] Config checks in the configuration overview admin page
  • [x] Problem detection in the admin email digest is handled

• Release management

  • [x] I have labelled the PR as "needs-backport" accordingly

• I have updated the translations assets (you do NOT need to provide translations)

  • [x] Ran ./bin/makemessages_js.sh
  • [x] Ran ./bin/compilemessages_js.sh

• Commit hygiene

  • [x] Commit messages refer to the relevant Github issue
  • [x] Commit messages explain the "why" of change, not the how

[sergei-maertens]

So one particularly interesting observation is that in the hottest code path and logic rule evaluation there seems to be much more room for improvement.

With the master branch, 58% of time was spent in glom, and there were about 18,5K calls to it. In this patch, 34% of time is spent in glom, and there are still about 15K calls - so only about 3K calls are stripped away. It could be that many of those led to exception handling and that caused the slowdown, but I can't even begin to imagine what performance is left uncovered if we can bring those 15K to 1K calls, for example.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 96.57%. Comparing base (751991d) to head (d2bd3cf). Report is 4 commits behind head on master.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #4768 +/- ## ======================================= Coverage 96.56% 96.57% ======================================= Files 746 746 Lines 25210 25223 +13 Branches 3322 3325 +3 ======================================= + Hits 24345 24358 +13 Misses 602 602 Partials 263 263 ```

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[sergei-maertens]

Validated and approved by DH - it's not up to OF 2.6.x levels yet, but a vast improvement over 2.7.x.

[sergei-maertens]

Backports:

• 2.8.x: 6ed8a2d23803c59239f51b9ffd07b746a22a1a6d, bd44c1338604bb0ba659a824e747724103fbf026
• 2.7.x: 63528a8a94ffba2d51ac41c9b8e4155bf95fde57