v1.5-beta: instalation build errors

[interduo]

1. Useles file created
   root@libreqos-beta:/opt/libreqos# ls -la
   total 16
   drwxr-xr-x 3 root root 4096 Jul 1 08:46 .
   drwxr-xr-x 3 root root 4096 Jul 1 08:45 ..
   -rw-r--r-- 1 root root 85 Jul 1 09:09 '='
   drwxr-xr-x 4 root root 4096 Jul 1 09:10 src

root@libreqos-beta:/opt/libreqos# cat '='
Requirement already satisfied: setuptools in /usr/lib/python3/dist-packages (68.1.2)

2. Error about not existed package

ERROR: Could not find a version that satisfies the requirement 65.5.1 (from versions: none)
ERROR: No matching distribution found for 65.5.1
ERROR: Could not find a version that satisfies the requirement 65.5.1 (from versions: none)
ERROR: No matching distribution found for 65.5.1

This comes from HERE: https://github.com/LibreQoE/LibreQoS/blob/main/requirements.txt#L12

I suggest to:

1. add requirements.txt to deb package
2. here https://github.com/LibreQoE/LibreQoS/blob/main/src/build_dpkg.sh#L64-L68 use syntax like python3 -m pip install -r requirements.txt and remove loop

[interduo]

PR fixing this issue was merged (#510).