Update maintainer list

[skip ci]

libs/maintainers.txt

@@ -32,7 +32,7 @@ compute               Kyle Lutz <kyle.r.lutz -at- gmail.com>
 concept_check         Jeremy Siek <jeremy.siek -at- gmail.com>
 config                John Maddock <john -at- johnmaddock.co.uk>
 container             Ion Gaztanaga <igaztanaga -at- gmail.com>
-container_hash        Daniel James <dnljms -at- gmail.com>
+container_hash        Peter Dimov <pdimov -at- gmail.com>
 context               Oliver Kowalke <oliver.kowalke -at- gmail.com>
 contract              Lorenzo Caminiti <lorcaminiti -at- gmail.com>
 conversion            Antony Polukhin <antoshkka -at- gmail.com>