deps: update lib-jitsi-meet

Changelog:
6502bc67 Wed Apr 15 10:51:35 2020 +0200 Philipp Hancke: e2ee: generate silence in case of audio decryption errors
adc87bcf Mon Apr 6 15:07:48 2020 -0500 paweldomas: fix(strophe.jingle.js): exception on ICE config modification

package-lock.json

       }
     },
     "lib-jitsi-meet": {
-      "version": "github:jitsi/lib-jitsi-meet#5423a24f18c28b7c15cbe6bd0fc610c55ed756d1",
-      "from": "github:jitsi/lib-jitsi-meet#5423a24f18c28b7c15cbe6bd0fc610c55ed756d1",
+      "version": "github:jitsi/lib-jitsi-meet#70a3298914f3905297e4e9dcc200b95e9b7a73e9",
+      "from": "github:jitsi/lib-jitsi-meet#70a3298914f3905297e4e9dcc200b95e9b7a73e9",
       "requires": {
         "@jitsi/sdp-interop": "1.0.1",
         "@jitsi/sdp-simulcast": "0.3.0",

package.json

     "js-utils": "github:jitsi/js-utils#df68966e3c65b5c57fcd2670da1326a2c77518d1",
     "jsrsasign": "8.0.12",
     "jwt-decode": "2.2.0",
-    "lib-jitsi-meet": "github:jitsi/lib-jitsi-meet#5423a24f18c28b7c15cbe6bd0fc610c55ed756d1",
+    "lib-jitsi-meet": "github:jitsi/lib-jitsi-meet#70a3298914f3905297e4e9dcc200b95e9b7a73e9",
     "libflacjs": "github:mmig/libflac.js#93d37e7f811f01cf7d8b6a603e38bd3c3810907d",
     "lodash": "4.17.13",
     "moment": "2.19.4",