app/matrix: bump riot to 1.7.29

Change-Id: I26c99f110abb7a68320587d7056558403b34a122
diff --git a/app/matrix/lib/matrix-ng.libsonnet b/app/matrix/lib/matrix-ng.libsonnet
index 7dfc8ef..95e9257 100644
--- a/app/matrix/lib/matrix-ng.libsonnet
+++ b/app/matrix/lib/matrix-ng.libsonnet
@@ -63,7 +63,7 @@
 
         images: {
             synapse: "matrixdotorg/synapse:v1.35.1",
-            riot: "vectorim/riot-web:v1.7.18",
+            riot: "vectorim/riot-web:v1.7.29",
             casProxy: "registry.k0.hswaw.net/q3k/oauth2-cas-proxy:0.1.4",
             appserviceIRC: "matrixdotorg/matrix-appservice-irc:release-0.26.0",
             appserviceTelegram: "dock.mau.dev/tulir/mautrix-telegram@sha256:c6e25cb57e1b67027069e8dc2627338df35d156315c004a6f2b34b6aeaa79f77",