fix(fuel): turnaround fuel used reset

[Taz5150]

Fixes #6862 (partially)

Summary of Changes

With the new EGT cooling constant, the engine maintains a "shutting" state for a long time (instead of switching to "off" state once N2 gets to zero). Due to this change in the engine state model, fuel used was not being reset. This issue is being solved with this PR.

Screenshots (if necessary)

References

Additional context

Discord username (if different from GitHub): TazX [Z+2]#405

Testing instructions

One way to do it:

1. Start aircraft on runway
2. Switch SD to ENG and burn some fuel (until it is shown in the SD)
3. Turn Engine 2 OFF (Master Off) and let it roll back
4. Switch igniter ON
5. Start Engine 2
6. Used fuel should reset to 0

How to download the PR for QA

Every new commit to this PR will cause a new A32NX artifact to be created, built, and uploaded.

1. Make sure you are signed in to GitHub
2. Click on the Checks tab on the PR
3. On the left side, click on the bottom PR tab
4. Click on the A32NX download link at the bottom of the page

[johnpmaguire]

Tested this in the usual situations where an engine would be shut down on the ground. Restarted the engine and fuel used was reset to zero. Tested both eng 1 and 2. Also tested in the air. System worked as expected fuel used was not reset to zero in the air.

A nice fix to a couple of questions in the support channel recently. Exceptionally efficient code change.

Looks good to go to QA if needed probably does not.

[Saschl]

Just a small remark (not related to this PR).

I noticed https://github.com/flybywiresim/a32nx/blob/eae165b508f398a07c92bd1e340eba8db37f455a/src/fadec/src/EngineControl.h#L1126 animationDeltaTime is never initialized. You probably wanted to use the class member animationDeltaTime here?
https://github.com/flybywiresim/a32nx/blob/eae165b508f398a07c92bd1e340eba8db37f455a/src/fadec/src/EngineControl.h#L18

Anyway not related to this PR but I thought I'd note it.

[mico975]

Quality Assurance Tester Report

Discord : mico#3145
Object of testing: #6876
Tier of Testing : 1
Date : 10/03/2022

Testing Process:
Started the engine, shut down the engine, restarted the engine and fuel got reset. It works. 🚀
Does not work in the air, as intended.

Negatives:
N/A

Testing Results:
Passed

Conclusions:
Magnificent efficiency in coding 🤣

[Taz5150]

Just a small remark (not related to this PR).

I noticed

https://github.com/flybywiresim/a32nx/blob/eae165b508f398a07c92bd1e340eba8db37f455a/src/fadec/src/EngineControl.h#L1126

animationDeltaTime is never initialized. You probably wanted to use the class member animationDeltaTime here?
https://github.com/flybywiresim/a32nx/blob/eae165b508f398a07c92bd1e340eba8db37f455a/src/fadec/src/EngineControl.h#L18

Anyway not related to this PR but I thought I'd note it.

Your are completely right. I used to work with animationDeltaTime to detect pauses, but that is obsolete now. Will make changes in subsequent PRs (need to make sure there is nothing depending on that variable).

Thanks!!!