Memory Leakage: if setPlots get called multiple times, TreeModels get allocated and the pointer gets overwritten

Requirements

• I searched through the issues if the issue already exists

Steps to reproduce

Expected

No Memory Leakage

Observed

Labplot Version

Release build 2.10.0-693-g3cdd8b01a
Aug 14 2023, 10:24:16
System: Windows 11 Version 2009
Locale: English,United States (Decimal point '.', Group separator ','
Number settings: Decimal point '.', Group separator ',', Exponential 'e', Zero digit '0', Percent '%', Positive/Negative sign '+'/'-' (Updated on restart)
Architecture: x86_64-little_endian-llp64
Kernel: winnt 10.0.22621
C++ Compiler: MSVC 19.29.30148.0
C++ Compiler Flags: /DWIN32 /D_WINDOWS /GR /EHsc /wd4250 /wd4251 /wd4396 /wd4661 /Zc:__cplusplus -O2 -W3 -DPSAPI_VERSION=1