fix: Fixed fake_matrix_api.dart signedOneTimeKeys upload

lib/fake_matrix_api.dart

@@ -2006,8 +2006,9 @@ class FakeMatrixApi extends MockClient {
       '/client/v3/keys/upload': (var req) => {
             'one_time_key_counts': {
               'curve25519': 10,
-              'signed_curve25519': tryCast<Map<String, Map<String, Object?>>>(
-                          decodeJson(req))?['one_time_keys']
+              'signed_curve25519':
+                  tryCast<Map<String, Object?>>(decodeJson(req))
+                          ?.tryGetMap<String, Object?>('one_time_keys')
                           ?.keys
                           .length ??
                       0,

pubspec.yaml

@@ -19,3 +19,8 @@ dev_dependencies:
   import_sorter: ^4.6.0
   lints: ^2.0.0
   test: ^1.14.4
+ 
+dependency_overrides:
+# uncomment for local development
+#  matrix:
+#    path: '../famedlysdk'