Update seeds

Summary: See title.

Test Plan:
ninja check

TOTAL=$(cat nodes_main.txt | wc -l); NUM=$(./test-seeds.sh < nodes_main.txt | wc -l); echo "scale=3; $NUM / $TOTAL" | bc
92.1% connectivity from my local machine

TOTAL=$(cat nodes_test.txt | wc -l); NUM=$(./test-seeds.sh --testnet < nodes_test.txt | wc -l); echo "scale=3; $NUM / $TOTAL" | bc
100% connectivity from my local machine

Reviewers: #bitcoin_abc, deadalnix, Fabien

Reviewed By: #bitcoin_abc, Fabien

Differential Revision: https://reviews.bitcoinabc.org/D4652