⬆️👽 update to latest MQT Core version

[burgholzer]

Description

This PR updates the MQT Core version used in QCEC to the latest version. This includes changes from cda-tum/mqt-core#674 and cda-tum/mqt-core#764.
SWAP eliding is now performed explicitly in QCEC instead of implicitly in the getDD method of MQT Core.
Furthermore, states generated by the DD package now have their ref count increased by default, which required subtle changes to the ref counting scheme.

Checklist:

• The pull request only contains commits that are related to it.
• I have added appropriate tests and documentation.
• I have made sure that all CI jobs on GitHub pass.
• The pull request introduces no new warnings and follows the project's style guidelines.

[codecov]

Codecov Report

Attention: Patch coverage is 94.11765% with 1 line in your changes missing coverage. Please review.

Project coverage is 95.7%. Comparing base (0ed735c) to head (4c57cfd).
Report is 4 commits behind head on main.

Files with missing lines	Patch %	Lines
include/checker/dd/TaskManager.hpp	91.6%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##            main    #531     +/-   ##
=======================================
+ Coverage   95.5%   95.7%   +0.1%     
=======================================
  Files         40      40             
  Lines       1832    1840      +8     
  Branches     224     225      +1     
=======================================
+ Hits        1751    1762     +11     
+ Misses        81      78      -3     

Flag	Coverage Δ
cpp	96.3% <94.1%> (+0.2%)	⬆️
python	93.7% <ø> (ø)

Files with missing lines	Coverage Δ
src/checker/dd/DDAlternatingChecker.cpp	98.6% <100.0%> (ø)
src/checker/dd/DDSimulationChecker.cpp	100.0% <100.0%> (ø)
src/checker/dd/simulation/StateGenerator.cpp	94.9% <100.0%> (+<0.1%)	⬆️
include/checker/dd/TaskManager.hpp	97.2% <91.6%> (-1.3%)	⬇️

... and 2 files with indirect coverage changes