Addressable content build fails with “Object reference not set to an instance of an object” when rebuilding Addressables after entering and exiting Play Mode with groups using custom Build/Load paths

Reproduction steps:
1. Open the attached project “IN-139010“
2. Go to Window > Asset Management > Addressables > Groups
3. Build the Addressables (via Addressables Groups window: Build > New Build > Default Build Script)
4. Enter Play Mode
5. Exit Play Mode
6. Build the Addressables again
7. Observe the result

Actual result: Addressables build fails with “Object reference not set to an instance of an object”
Expected result: Addressables build successfully

Reproducible with: 1.22.2 (2023.3.0a2), 2.10.1 (6000.0.73f1, 6000.3.14f1, 6000.4.4f1, 6000.5.0b5, 6000.6.0a3)
Not reproducible with: 1.21.21 (2023.3.0a2)

Reproduced on: Windows 11 Enterprise
Not reproduced on: No other environment tested

Workarounds:

• Restart the Editor before rebuilding Addressables
• Refresh the Addressables groups that use custom Build/Load paths before building again