[Bug] Switching from unity 6.2 to 6.3 causes iOS builds to fail due to missing development team signing

### Description

Recently I updated my unity project from 6.2 to 6.3. After the update my build for iOS have started failing and I noticed firebase errors in the logs. I've experienced similar issues in the past and figured I just needed to update firebase. I updated firebase from 12.7 to 13.10 but the build still has issues. I have tried unity support and searching other places but I am unsure how to force firebase to properly sign the development team.

`[error] [2026-04-21T17:45:52.904Z] - 7.6.41.3.3.5 - INFO: ▸ /BUILD_PATH/Library/Developer/Xcode/DerivedData/Unity-iPhone-fawtmnmyvhlglwbxrjntbhbhlqtu/SourcePackages/checkouts/firebase-ios-sdk/Package.swift: error: Signing for "Firebase_FirebaseCrashlytics" requires a development team. Select a development team in the Signing & Capabilities editor. (in target 'Firebase_FirebaseCrashlytics' from project 'Firebase')
[warning] [2026-04-21T17:45:52.904Z] - 7.6.41.3.3.5 - INFO: ▸ /BUILD_PATH/apex-innovations.nihss.ios_beta_build/temp20260421-2612-orgpy7/Unity-iPhone.xcodeproj: warning: tasks in 'Copy Headers' are delayed by unsandboxed script phases; set ENABLE_USER_SCRIPT_SANDBOXING=YES to enable sandboxing (in target 'UnityFramework' from project 'Unity-iPhone')
[warning] [2026-04-21T17:45:52.904Z] - 7.6.41.3.3.5 - INFO: ▸ warning: Run script build phase 'Crashlytics Run Script' will be run during every build because it does not specify any outputs. To address this issue, either add output dependencies to the script phase, or configure it to run in every build by unchecking "Based on dependency analysis" in the script phase. (in target 'UnityFramework' from project 'Unity-iPhone')
[error] [2026-04-21T17:45:52.904Z] - 7.6.41.3.3.5 - INFO: ▸ /BUILD_PATH/Library/Developer/Xcode/DerivedData/Unity-iPhone-fawtmnmyvhlglwbxrjntbhbhlqtu/SourcePackages/checkouts/GoogleUtilities/Package.swift: error: Signing for "GoogleUtilities_GoogleUtilities-Network" requires a development team. Select a development team in the Signing & Capabilities editor. (in target 'GoogleUtilities_GoogleUtilities-Network' from project 'GoogleUtilities')
[error] [2026-04-21T17:45:52.904Z] - 7.6.41.3.3.5 - INFO: ▸ /BUILD_PATH/Library/Developer/Xcode/DerivedData/Unity-iPhone-fawtmnmyvhlglwbxrjntbhbhlqtu/SourcePackages/checkouts/promises/Package.swift: error: Signing for "Promises_FBLPromises" requires a development team. Select a development team in the Signing & Capabilities editor. (in target 'Promises_FBLPromises' from project 'Promises')`

### Reproducing the issue

_No response_

### Firebase Unity SDK Version

13.10

### Unity editor version

6000.3.10f1

### Installation Method

.unitypackage

### Problematic Firebase Component(s)

All

### Other Firebase Component(s) in use

_No response_

### Additional SDKs you are using

_No response_

### Targeted Platform(s)

Apple Platforms

### Unity editor platform

Windows

### Scripting Runtime

Mono

### Release Distribution Type

Pre-built SDK from https://firebase.google.com/download/unity

### Relevant Log Output

```shell

```

### If using CocoaPods for Apple platforms, the project's Podfile.lock

Expand Podfile.lock snippet

```yml

👀 Replace this line with the contents of your Podfile.lock!

```

Start by reproducing the Unity 6.2-to-6.3 iOS export with Firebase Unity SDK 13.10 and inspect the generated Unity-iPhone Xcode project and the listed Package.swift signing errors. Compare signing settings for Firebase_FirebaseCrashlytics, GoogleUtilities_GoogleUtilities-Network, and Promises_FBLPromises; done means the iOS build completes without those signing errors.

Written by the indexing model from the issue text.