Several test scripts define a subclass of P2PInterface called TestNode.
This commit renames those to TestP2PConn since we already have a
TestNode class in the test framework.
-BEGIN VERIFY SCRIPT-
sed -i s/TestNode/TestP2PConn/ test/functional/*py test/functional/test_framework/comptool.py
_END VERIFY SCRIPT-
Backport of Core PR12728
https://github.com/bitcoin/bitcoin/pull/12728/files