A memory leak occurs during real-time precise point positioning

[2533672343]

Describe the bug Running multi-station real-time precision point positioning has the problem of memory leak.

To Reproduce Steps to reproduce the behavior:

1. ./../bin --config ex15_pea_rt_user_gnss_ar.yaml
2. Enter the 'top' command on the terminal, and you can see that the VIRT value continues to increase.

Expected behavior The amount of memory used during program execution does not always increase over time.

Configuration files ex15_pea_rt_user_gnss_ar.yaml, and the ambiguity_resolution is off, delete_old_ephemerides is true.

Desktop (please complete the following information):

• OS: Linux 20.04
• Version of Ginan:1.5.4
• Library used (Boost, Eigen, ...)