eol: make [eol] config section sensitive for chg confighash

The eol extension may mangle the [eol] config section and that means chg is
unable to detect config file change (because it re-applies setconfig
changes).

This makes test-eol.t pass with chg.

Differential Revision: https://phab.mercurial-scm.org/D917

mercurial/chgserver.py

@@ -68,6 +68,7 b' def _hashlist(items):'
 # sensitive config sections affecting confighash
 _configsections = [
     'alias',  # affects global state commands.table
+    'eol',    # uses setconfig('eol', ...)
     'extdiff',  # uisetup will register new commands
     'extensions',
 ]