Use the beta release of the widget-api

package.json

@@ -62,6 +62,7 @@
     "jsrsasign": "^9.1.5",
     "matrix-js-sdk": "8.4.1",
     "matrix-react-sdk": "3.5.0",
+    "matrix-widget-api": "^0.1.0-beta.2",
     "olm": "https://packages.matrix.org/npm/olm/olm-3.1.4.tgz",
     "prop-types": "^15.7.2",
     "react": "^16.9.0",

yarn.lock

@@ -8373,6 +8373,11 @@ matrix-react-test-utils@^0.2.2:
   resolved "https://registry.yarnpkg.com/matrix-react-test-utils/-/matrix-react-test-utils-0.2.2.tgz#c87144d3b910c7edc544a6699d13c7c2bf02f853"
   integrity sha512-49+7gfV6smvBIVbeloql+37IeWMTD+fiywalwCqk8Dnz53zAFjKSltB3rmWHso1uecLtQEcPtCijfhzcLXAxTQ==
 
+matrix-widget-api@^0.1.0-beta.2:
+  version "0.1.0-beta.2"
+  resolved "https://registry.yarnpkg.com/matrix-widget-api/-/matrix-widget-api-0.1.0-beta.2.tgz#367da1ccd26b711f73fc5b6e02edf55ac2ea2692"
+  integrity sha512-q5g5RZN+RRjM4HmcJ+LYoQAYrB1wzyERmoQ+LvKbTV/+9Ov36Kp0QEP8CleSXEd5WLp6bkRlt60axDaY6pWGmg==
+
 md5.js@^1.3.4:
   version "1.3.5"
   resolved "https://registry.yarnpkg.com/md5.js/-/md5.js-1.3.5.tgz#b5d07b8e3216e3e27cd728d72f70d1e6a342005f"