FIX: Export configuration and AEDT crash

[maxcapodi78]

• export_configuration method was failing under certain circumstances
• aedt_objects were still referenced after a project was closed and could cause crash in AEDT during debug mode.

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[codecov[bot]]

Codecov Report

Attention: Patch coverage is 83.09859% with 12 lines in your changes missing coverage. Please review.

Project coverage is 83.34%. Comparing base (506637b) to head (e242c5f). Report is 5 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #4913 +/- ## ========================================== + Coverage 79.12% 83.34% +4.21% ========================================== Files 118 119 +1 Lines 54177 54328 +151 ========================================== + Hits 42869 45277 +2408 + Misses 11308 9051 -2257 ```