Readd segment to prevent FQN for older core versions

[helsner]

As upgrades often go step by step we should readd a commented segment. This should prevent the FQN change in the files:

'ext_localconf.php',
'ext_tables.php',
'ClassAliasMap.php',
__DIR__ . '/**/Configuration/*.php',
__DIR__ . '/**/Configuration/**/*.php',