Add explicit pytest.hookspec/hookimpl annotations, avoid legacy tryfirst/trylast marks

src/xdist/newhooks.py

@@ -14,18 +14,22 @@ must be taken in plugins in case ``xdist`` is not installed. Please see:
 import pytest
 
 
+@pytest.hookspec()
 def pytest_xdist_setupnodes(config, specs):
     """called before any remote node is set up."""
 
 
+@pytest.hookspec()
 def pytest_xdist_newgateway(gateway):
     """called on new raw gateway creation."""
 
 
+@pytest.hookspec()
 def pytest_xdist_rsyncstart(source, gateways):
     """called before rsyncing a directory to remote gateways takes place."""
 
 
+@pytest.hookspec()
 def pytest_xdist_rsyncfinish(source, gateways):
     """called after rsyncing a directory to remote gateways takes place."""
 
@@ -35,18 +39,22 @@ def pytest_xdist_getremotemodule():
     """called when creating remote node"""
 
 
+@pytest.hookspec()
 def pytest_configure_node(node):
     """configure node information before it gets instantiated."""
 
 
+@pytest.hookspec()
 def pytest_testnodeready(node):
     """Test Node is ready to operate."""
 
 
+@pytest.hookspec()
 def pytest_testnodedown(node, error):
     """Test Node is down."""
 
 
+@pytest.hookspec()
 def pytest_xdist_node_collection_finished(node, ids):
     """called by the controller node when a worker node finishes collecting."""