traefik: 1.5.0 -> 1.5.2

Semi-automatic update. These checks were performed:

- built on NixOS
- ran `/nix/store/byzavm86fdpdnigaj0j4r9bd755pqylq-traefik-1.5.2-bin/bin/traefik -h` got 0 exit code
- ran `/nix/store/byzavm86fdpdnigaj0j4r9bd755pqylq-traefik-1.5.2-bin/bin/traefik --help` got 0 exit code
- ran `/nix/store/byzavm86fdpdnigaj0j4r9bd755pqylq-traefik-1.5.2-bin/bin/traefik version` and found version 1.5.2
- found 1.5.2 with grep in /nix/store/byzavm86fdpdnigaj0j4r9bd755pqylq-traefik-1.5.2-bin
- found 1.5.2 in filename of file in /nix/store/byzavm86fdpdnigaj0j4r9bd755pqylq-traefik-1.5.2-bin

cc "@hamhut1066 @ehmry @lethalman"