[Phobos Bug] Negative ShieldType SelfHealing not working if shield has full strength

Description:

If shield has full strength, shield's negative SelfHealing doesn't work. The shield should deduct its strength at the time.
If this behavior is not actually a bug, I think it's confusing enough to be mentioned in doc.

Phobos Build:

https://github.com/Phobos-developers/Phobos/releases/tag/build-27

Conditions:

Ares3.0 + Phobos build27 (it appears in earlier builds too)

[ShieldTypes]
0=SOMESHIELDTYPE

[SOMESHIELDTYPE]
Strength=50
InitialStrength=50
Armor=none
Powered=false
AbsorbOverDamage=false
SelfHealing=-10
SelfHealing.Rate=0.1

[E1]
ShieldType=SOMESHIELDTYPE

There isn't any other INI changes.

Steps To Reproduce:

1.Enter the game and see GIs

Expected Behaviour:

GI's shield should reduce its strength at the time.

Actual Behaviour:

GI's shield doesn't reduce its strength unless GI was hit.

Additional Files / Links:

[Starkku]

Has a fix pending in PR #535. Feel free to test the nightly build linked in there and confirm if the fix works in the PR comments.